There are RV salvage yards out there, but they’re few & far between. You might try a Google search for them… and if you find one within a reasonable distance, make a phone call. That’s about the only help I can give ya. Good luck.
2013 VOLTAGE 3200 (EPIC I & II)
2014 Ford F-450 PLATINUM
2018 BMW R1200GS RALLYE
Several years back I had a piece of siding peel back while traveling. I found a place that did RV repair and the owner was able to find the siding that I needed. Unfortunately, he is out of business now or I would pass on his information to you. He had a large sample of different pieces to choose from.
You might check around your area for companies that do RV body repair. I am in the OKC area so you might with your insurance company. My insurance agent gave me his name. So, you might check with them.