I think a Zalman CNPS7000-Cu or Thermalright XP-90 should fit on there ok. I think a CNPS7700-Cu and XP-120 would be a little to big but there is no way of knowing w/o measuring. One of those would put a heafty ammount of copper on that cpu and give you a very good cooling to noise ratio.
If those are to big you will probably be ok with a GIGABYTE 3D Rocket cooler, that thing should do a decent job.
<A HREF="http://www.folken.net/myrig.htm" target="_new">My precious...</A>