If you are set on selling it, I might be interested. Ours has a few dings, barely functioning A/C and no furnace, but we towed it 2900 miles this summer.
As for buying another, we are signing up Airstream enthusiasts to inspect trailer for potential buyers. Check our database if you find one that's too far away from you to see if someone would be willing to look at it and take photos for you.
As for setting a price, just be honest about the trailer condition and list it on Craigslist. If it's under-priced you'll get 10 emails in an hour. Overpriced and nobody will email. About right and it should sell in a week. Start at $5000 and go from there.
1966 Streamline Countess 26'