Your best bet is to get a Thermaltake Giant III, IMO. I bought one last week as I stated in your last thread. It's a bit high in price (it just came out like 2-3 weeks ago) but, it's worth every penny. This baby has two heatpipes and already has 8 copper ramsinks included with it. My graphics card runs cooler at these overclocked speeds than what it did with at the stock speeds with the stock cooler.
I've gotten it to 485mhz x 380mhz (Core x RAM) instead of 378 x 337.5 which is the stock. With the original cooler I got it up to around 400mhz x 350mhz.
Here is a pic of mine,
here.