For people near Kansas City, check out Muscle Cars Inc. in Independence. Went there today and picked up a quarter skin. The cool thing is that they are a Goodmark distributor so you can get all your sheet metal without paying truck freight! My purchase today saved me over a $100. I talked to the owner and he is a really nice guy. He told me that they are mostly Ford and Chevy, but he is stocking more and more Mopar parts. For interior they use Legendary.
Btw, he told me he has the new $600 replacement quarters for Challengers. Thick metal, don't flex, and look just like a NOS part.