One here in Indiana has a ton of stuff, nearly anything a person would want,
Ickes RV surplus supply, 701 W Huntington St, Montpelier IN. 765 728-5668.
Also a manufacturer that builds ramp doors for toy haulers,
Challenger Door Co, (574) 773-0470,
1205 East Lincoln Street
Nappanee, Indiana 46550
challengerdoor.com