The stock heatsink is decent, as long as your case is good on vents, I have an old case with an i7 in, and 6gb ram and such, idles at about 41C now,but it has no intake and no exhaust capabilities, so literally its a hot box.
With proper air flow it should be fine- not overclocking.
Also- don't remove the thermal paste on the stock cooler- it works very well despite being "stock grease" on par with Antec 5, so there's literally no reason to remove/scrape it off to replace it with something of near similar performance.
With my new case I expect to drop degrees C a whole lot, some stated the max load being 72 right now, dropping to 56 with a good vent case.
And honestly due to the size of the heatsinks out there for these babies... If I do OC, I would just go liquid cool anyway, take up much less space and much easier to work with in the long run.