I haven't made my way there yet, but Elkhart IN is the place to go. RV Parts Nation is where I am going to check out new overstock items at low cost, and also the town has one or two RV Salvage yards. I am in Northern Indiana and there are also some places in Southbend IN. If you end up at these places soon let me know how the selection is. I don't plan on going until I have a full list of items I need for my RV remodel. Both cities are in northern indiana.
Scott, we were in the Elkhart area earlier this year. Don't miss the RV Hall of Fame and Museum. For surplus try here. http://www.rvsurplus.net/ Also, a few miles over the border in Michigan is this place which is open on Sunday's (the others are not). http://bontragers.com/ We spent several hours here. They have a big variety stacked up all over the place, and you just have to search for what you are looking for outside and in about 4 buildings. A HUGE inventory of replacement thermal windows for MHs and TTs and 5ers.
Factory RV Surplus is just a couple of blocks down from RV Surplus. Worth checking them both out, along with Bontragers'. They're about 10 miles out of town in farm country just across the Michigan state line.
In fact, doing a Google search on Elkhart and/or Michiana area RV surplus parts would be a good idea. I seem to remember a couple of smaller places, but it's been several years since I've been there and things may have changed.
And definitely check out the RV Hall of Fame and Museum if you're in the area. It's just off of the Indiana Toll Road (I-80) at Exit 96 and of course they have RV parking. They're sponsored by RVIA and with the downturn in the RV industry's fortunes it's rumored they're having financial difficulties and may have to close.