Hi Carl :
Avion, I believe, used to be made by the Avion Company, but some years back, it was acquired by Fleetwood, a large RV / mobile home company. They are still made, but the silver aluminum models were discontinued a number of years ago. You can find out about the new ones at:
I do not know what this one would be worth, but I think I've seen Airstreams in that year range and newer for a little less, so it seems about right or maybe a little high - It would depend on the true condition of the trailer.
A good resource for the value would be the Kelley Blue Book. "Travel Trailer Guide -- Covers 15 years of used travel trailers, fifth wheels, folding trailers, plus a chart for older models. Annual subscription $48. Published twice a year"
You can find this book at most banks or credit unions, and also at many bookstores.
Best,
Gary Mager
Reno, NV