maskedgeek, Sorry I don't have one that small available, but you can get a nice 80 watter (Ice-71 40mmx40mm) from www.tedist.com . It's $23 including quality potting. That's where I get mine from, and love the quality. You sure you want to skimp on the price?, your cpu may pay the difference man. (and then some) *edit* just saw it's not gonna be on the cpu...heh
f155mph, one of the reasons I buy from TE distributing is they have the specs listed for each unit. My 122 watter for example, will move 122 watts of heat. It will consume 12.4 amps at 15.9 volts, so that's 197.16 watts. (A x V = W)
So you're able to move 122 watts of heat with it, but you're adding 197 watts of the pelt's heat that has to be removed by the cooling system. Say the processor is only puting out 100 watts, that's almost 300 watts that the heatsink/waterblock has to be able to remove. That's why heatsinks can't usually hang with a pelt larger than 80 watts.
You can try searching the cooling threads or software threads for a program called radiate. It's supposed to be a database of cpu wattages. Pay close attention to detail when you go to insulate that puppy!
I'm a little more adventurous, and just guess...someday I'll probably be wrong, and fry that sucka! I wouldn't suggest you follow my example.