FFS...I just got a 612S for £32, typical. Would have ordered that True Spirit right away.
Definitely that one for that price, really good!
I've already installed it, it came next day as usual thanks to overclockers. Just would have picked the True 140 hands down.
If your case is going to be louder just wait till Haswell.
I think the stock heatsink would cope with that overclock tbh. Can always wait it out? You have free postage anyway why not just order after you try overclock with the stock hsf?
I use a Xigmatek Gaia on my i5 3570K in a Coolermaster Silencio 550 case. It run's pretty much silent, though these are not the best case's if you plan to do any serious overclocking.