Non-k CPUs have a locked multiplier which means you can only overclock by changing the BCLK which can cause other issues to occur, but can be done. I'm assuming you have all the info handy to do so? What are you attempting to reach and at what settings?
In all honesty, both human and hardware ability are usually the limiting factor to overclocking temps and stability than cooler performance. That being said, any decent air or liquid cooler should meet your needs. Can you provide some details on what you're looking at?