Bear in mind that a the current generation of these, the Virtex 6, starts at about $800 for the smallest parts and I believe goes well over $20k for the larger ones. Expect the Virtex 7 to be priced in this ballpark.
edit: I was off by an order of magnitude on the high end. $2k -> $20k
edit: I was off by an order of magnitude on the high end. $2k -> $20k