Axle

Please post some pictures, it will help us help you better / more easily...

PHOTO TUTORIAL LINK

Whitney

20211223_120743 by Austin Olesak, on Flickr

20211223_120719 by Austin Olesak, on Flickr

To me, your axle looks like most 50+ yr old axles.  Some wire brushing, rusty metal primer, some paint, and it should be fine after inspecting, cleaning, replacing what needs replaced on the brakes and bearings.  Don't forget to replace the grease seal in the hubs, over 50 yrs old, yep, it time.  I replaced my axle because the threads on my spindle were boogered up and I had an axle, just had to narrow it a bit.

As far as the springs go, the common opinion is to replace them do to the "less than arching" (dip-de-doodle) sag where it bolts to the axle.  This, in a nut shell, is metal fatigue after, again, 54 yrs of the weight of the camper sitting on it whether it has been pulled 50 miles or 50k miles.
Mine on my '67 Compact look similar.  For now, I disassembled my (unstacked them), cleaned, painted, and applied a lubricant between the leaves before reassembly.  May replace at a later time.
If there are any leaves that are broke or cracked, definitely replace both sides.

OK, here's the catch:  If you choose to rebuild, and your '67 Shasta springs are like my '67 Shasta springs, the spring eyes have a rubber and metal sleeved bushing.  Can't just order them and I went through every control arm bushing in the auto parts store that I work at with no matches that were close enough to use.  I ended up making a new set of bushing from nylon bushing material.  Not a bad job, not too time consuming, just, well, ya...

On the other hand:  Replacing the springs with new ones will give you new metal, standard "modern" bushings, and hopefully; reliability along with restoring ride height.
Catch to this one is; chances of you finding an exactly matching (measured) set of springs that will work in your existing spring hangers are very slim.  New spring hangers will need to be welded on, which isn't the end of the world, just wanting to make you aware.  Depending on where you live will depend on how much trouble it is to find someone to perform this task.

Oh ya, don't forget new U-bolts to hold the axle to the springs and spring bolts (hold spring to trailer frame)

Hope I didn't scare you.  I probably said too much or not enough.
And as always, it's just my opinion, didn't say it was a good one...
Whitney

Just for reference, here's what mine looked like:



The rubber & metal sleeve bushing the used at the factory.  I like this idea, it was a good idea to smooth out the ride & reduce noise, but would be nice if it had an easily sourced replacement.  There was another member of this site several years ago that actually found a replacement, but they haven't been on the site in a while and I had no luck contacting them.


And my final results (ya, I see that I didn't get enough paint on the u-bolt)
My springs have a flat spot above the axle but I went ahead and reused them for now.  I replaced the U-bolts, nuts, and welded a spring seat on the axle so I could move it to under the leaf springs.  By moving the axle under the springs, this added 4 1/2" in height / ground clearance because the Compacts set so low.  I left the original, so if I don't like it, I can always put it back.
I used "slip-plate" (graphite) paint between the leaf's (leaves?) after painting.  Some use a layer of grease.
Even though I replaced my axle with a different one, they were in similar rust covered state.  I replaced the axle because (pay attention, this is where it gets confusing): 1. the spindle threads on the original was boogered up 2. I widened the frame 4 1/2" so I could fit a queen size bed sideways  3. this axle had brake assemblies which I really would like to add to this trailer (I've pulled my teardrop in the mountains without brakes for far too long, I WANT BRAKES)  4. this axle was a wee bit heavier duty.


Golly, I get long winded.
Anyway, as always, it's just my thoughts and opinions, didn't say they were good ones...
Whitney

As for finding rubber bushings, go to a spring shop not a parts store. Parts stores cover vehicle specific bushings, spring shops deal with more standardized stuff and go by dimensions vs applications.

I prefer rubber vs metal bushings.

Funny thing about leaf springs vs coils or torsion, the inter leaf friction creates a bit of a self dampening effect. Therefore shocks are less critical for leaf springs vs others.