There is an awful lot of cheaper product available but as it's junk I'm not shipping it, unless the receiving end is 100% clear on it being them having the issue not me when it goes kerploof.
Those 5870s for example: I have shipped a pair of them to what I consider trusted forum members for testing, yes at my expense as I was wondering if they'd cooked up extra nice samples for me, and as a result they aren't being offered atm until the supplier answers an awfully long list of nasty questions I've sent them.
Try PMing me some of the stuff you're looking for. Especially with brnad names and numbers and I'll see what I can find.
You are not supposed to ask those kinds of questions to counterfeit manufacturers. Bad things will happen.