Although not a store, I've always had great experiences with Alan Swaim, ebay id: bigpavb. Mostly lower grade, raw T206's. And his auctions all tend to end on sundays at 8 pm central.
And as stated in previous posts, the following are all top notch:
Tom Barlage
David Bryan
Mike Wheat
joesvintage...
buythatcard
greenmonster
just_collect
T206-HolyGrail...
Edited to add that I've heard ebay seller harrywright is also great to deal with ... i think he even posts on this forum every now and again