As far as quality, you're going to get pretty much the same thing from everyone. I've used
Jim Carter in Independence, MO for quite a bit of stuff, and lately I've used
The Filling Station in Oregon because of the proximity to me. Also available is
Chevs of the 40's in Vancouver, WA who have had parts I needed that other vendors didn't. For stuff like trim and hardware,
Restoration Specialties in PA is my go-to. I guess what I'm saying is shop around.Even LMC has some good deals on proper parts (parking brake cables for one).
I'll see if I can track down a vendor list link for you. [on edit]
HERE YOU GO.