Hi Alison, and welcome to the nut house. I am really glad that you are stopping in to hunt for some answers. You have found a group here that will tell it like it is and will seriously answer your questions, even if you don't like the answers. Brace yourself!
Let me be the first to take a crack at this one. (Okay, so I got long-winded and didn't make it here first...)
First, before you get much further searching out a vintage trailer, my suggestion is to do some research. I am guessing that you have not had a lot of time looking around in depth here, or at any other resources that would point out what it is you are getting into. A quick trip into Larry's videos at http://www.cannedhamtrailers.com can be very enlightening. Vikx, our resident forum-guru and knowledgeable-type person who does some restoration work has an e-book available ( be damned if I can find the bookmark for the address for it right now...help!)
There are also numerous blogs and postings here on the forum of Airflytes that have been taken down and restored (or not) that can give you a real "inside" look at the one you are talking about purchasing.
I put all this out there first because in fact, there is no real "blue book" or definite pricing guide for real vintage trailers. They will sell on two basic principles: first, how long is an owner willing to hold out, and second, how much is a buyer willing to pay? Being very educated about what it is that you are getting yourself into is your best first move.
Now, as to the Airflyte...
I have a '64, and I have seen its bones and its guts. I can shed a little insight if you are willing to hear.
Taking only from what you have said here, and sight unseen:
First flag: "Interior water damage looks old and doesn't appear to have new damage. " It does not matter how new or old water damage is, it still will need to be repaired properly. It is the same extensive job either way.
Next flag: "Basically, it's a shell which is fine with me as we can restore it as we desire." There is nothing wrong with the idea of restoring to a personalized platform, but remember that each piece of cabinetry, bed-framing, door framing, table-hanging, all of the interior, is designed to enhance the structure of the whole unit. "Gutting" a trailer is the equivalent of destroying the structural integrity of the whole unit. This makes it much more susceptible to blowing apart on the freeway. Be very careful about how you intend to re-design any vintage trailer.
Next flag: " new exterior lights", "Comes with 2 sets of towing lights", " The brake wiring is in place, but it doesn't go to the front (not sure what the issue is - neither did the owner)"....... This is an indication that it will need all of the tow wiring harness reworked and probably replaced. Don't let that scare you, it isn't brain surgery, just be aware that it is a cost that needs to be figured into your restoration project. The brakes are likely to not have been functioning for years, and that should also be considered for replacement, which is another piece of that puzzle.
Next flag: " the door needs repair, the small side doors need to be repaired as well as the door framing on the camper"
Be advised that the frame of the entry door is quite affected by the likely almost positively leaking front side windows above the dinette seats. The design of these windows was destined to fail and leak and almost always always did. This means there is also liable to be damage to the paneling behind the cushions of the dinette, the framing in the walls, including sill boards, on either side as far back as the door frame. You will need to look for soft wood in the floor in the entryway as well. If that exists, you are talking a whole 'nother ball of wax.
Next flag: "Comes with.... a brushed nickel circular chandelier "
There's a reason vintage trailers were not originally fitted with chandeliers.... Please tell me you are considering this a plus only because you need a new light in your hallway or your toolshed.
There are a few positives...new tires, but be sure they are trailer-rated tires and not passenger-car tires. Even with new tires however is not a guarantee the wheel bearings have been checked or greased. The fading wood veneer interior is probably birch paneling, nearly impossible to find 1/8" thick for replacement, and it has to be replaced by removing the roof and doing work from the outside in. Very extensive work to do it right, but on the other hand, there are techniques for refinishing the shellac that can give wonderful results without replacing everything. Rotted panels will have to be replaced though, and it nets being the same job whether replacing a single panel or the entirety.
New sealant for windows should never come in a tube. Caulk and goop is a no-no. Sealing windows in something this old probably includes rebuilding the windows themselves to some extent, and new seals and stripping is available from a few different sources. Sealing the windows in place is done with putty tape.
Roof repair is probably leakage around the vent, which is repaired in the same way the windows are.
Remember, I am critical so that you can go into this with an educated opinion. "Forewarned is forearmed."
I would rather not offer an opinion on real dollars and cents for a purchase price, being sight-unseen and not knowing what lies underneath in the skirt boards. Nor do I know the asking price or the framework that you would consider reasonable for initial investment, added to cost of restoration.
Again, do your homework! There are lots of threads here on the forum to see how pricing can be established, as well as what the costs might run into for a proper restoration.
There's a reason vintage trailers were not originally fitted with chandeliers.... Please tell me you are considering this a plus only because you need a new light in your hallway or your toolshed. 
