You're in the happy hunting ground for gently used Airstreams. There are two "Airstream Only" parks in Texas where you'll find many retiree units. Of course, there comes a time when those units are up for sale. I've visited three such parks over the years and at every one there were units for sale. In the drier south west there are fewer problems with floor rot too. Also Airstream of Arkansas is one of the best in the country - A bit of a trip for you - depending on where in Texas you are. I hope you've found the classifieds here. Again a good place to start.
Good luck finding your first Airstream!
Today is a gift, that's why they call it the present.