[jchcollins]

I would just stick with reputable dealers on eBay who have a track record of selling accurately graded raw cards at reasonable prices. Spend some time looking at their feedback, and you should be able to tell. You could even find someone with 100% positive feedback that has an open ended return policy. In terms of specifics, I'm sure many on N54 could provide recommendations, and you could even find people in the BST forums here that come highly recommended. The goal with midgrade raw cards I would think would be to find them for cheaper raw than in PSA slabs. But depending on what grade you are looking for with vintage, you may want to look at graded; you might be surprised. Many PSA 4-6 range cards even of HOF'ers sometimes don't sell for markedly more than a raw copy of the same card in the same condition range.