You'll be able to fit a Noctua NH-D14, which is the probably the best air cooler you can get right now. You'll lower temps a bit, whch may in turn lower noise but noise itself is due to the fans. Now if temps are lower the fans should throttle back for less noise, but ultimately if you have quiet fans it won't change much in terms of noise. You'll see maybe another 3-5°C difference, whether that's worth an $80 purchase is up to you. You can probably squeeze another few more degrees if you go to a H100/H100i, but you still have to purchase quiet fans.
You want performance and quietness? Go with custom water cooling.
EDIT: I noticed you said you were on stock voltage. Why are you worrying about heat if you're not upping the vcore? You might be able to eek a bit more performance at stock with cooler temps but bumping up the voltage will give you a lot more result (and heat).
San Francisco: ASRock Z87E-ITX | Intel i7-4770k | 16 GB DDR3 1600 | Gigabyte WF3 7950
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Last edited by Eureka; 11-13-2012 at 11:54 AM.