Check out this site:
www.rvtraderonline.com
Lots of Airstreams, some Avions, and others for sale. Just go to the Browse button, plug in the years you want to search for and hit the "Travel Trailers" button.
PS - It's a sort of sequential process, so I usually let it pull up the Airstreams it has to show; and then do a right-mouse click to open a separate page for any particular unit I'm interested in. Usually at least one picture is included and also a link to the dealer or whomever is selling. Fun stuff. Some are probably also on eBay.
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