I don't have a specific recommendation for you, but can say that liquid cooling does exist for GPUs. Chances are good you'll have to build a custom loop to achieve what you're looking for, and it won't be cheap. Watercooling is typically a very poor value, generally performing worse and being louder at the same price point because of the added complexity, and with very high-end setups only being a little better than much cheaper air cooling options. However if noise or performance is not your concern, but aesthetics, I'd like to point you toward Swiftech's stuff. Their pumps are reliable, their radiators perform well and look good, and their blocks are among the best that aren't terribly expensive.