Maximum PC

I have an older Athlon II x2 260. I have just gotten my hands on my Phenom II x4 955 Black Edition. I made the mistake of getting the OEM edition of the Phenom. Can I use the Athlon heatsink on the newer chip? If not, will replacing the fan make it work better?
I am limited to fans from this site: http://www.memoryexpress.com/
The reason for this is that they are local, rather than me paying for shipping and waiting a week just for a fan. I was thinking of getting an 80mm to 120mm adapter and mounting a good 120mm fan to the old heatsink. Or getting the Cooler Master 212 Evo.
Which is the better option?

Chances are no, as the heatsink probably doesn't meet the TDP cooling requirements. Just get an aftermarket one.

212 Evo it is. What would be a good second 120mm fan to mount on it? I am looking for quiet operation, as my current 5 120mm fans are deafening when I crank up my cpu. I already have splitter and extension cables for hooking 2 fans up to my pwm fan header.