History of a 1954 Bel-Aire trailer, Where do I go from here?

I have the title & VIN of this 1954 Bel-Aire 15 ft. trailer. Wanting more history of it's previous life, I completed the "Request for Vessel record" attached a check I mailed it off to the Calif. DMV. What I received from the DMV was previous owners names & dates of ownership but no City information. The title say's original sale date of 1954, but the DMV  history only goes back to 1979. My question NOW is Who manufactured the Bel-Aire Trailer, Where was it manufactured, how many trailers did they produce? I've spent hours searching the web, and only found a similar name Bel-Aire Coach company-but it looked as if they produced park size models. Where do I go from here? Any information would be so much appreciated! If there was a plate with any identification it's under the diamond plate.....now.