So I've been looking on this site, wondering if its legit. Similar to alibaba I hear, but unsure. They have a buyer protection scheme, similar to eBay.
http://www.dhgate.com/product/wholesale-new-gtx-780-4g-4096mb-video-card/258793932.html#s1-0-1b;searl|3185163445
http://www.dhgate.com/product/wholesale-new-gtx-780-4g-4096mb-video-card/258793932.html#s1-0-1b;searl|3185163445