If an auto supply place doesn't have it, you could try an aircraft supply place, just ask for an anchor nut in whatever size it is. Could also try someplace like Fastenall....Phil.
Ace hardware might have, no matter what the price, it will be better than what it cost the PO at dealer to install new ones. I took the bolts into the shop and ground the bolts down to a point so that it is easier to find the hole and use fingers to tighten at least a couple of turns before using a wrench.
Bill Didn't want to infer you couldn't install the rivnut I gave you the link too. I posted and then decided to find a link for you and didn't proof read my post. Sorry!! Last time I used one it was not this simple, It required a tool that was about $200. The video makes it look simple now. Good luck with your repair.
This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.