The 212 evo is sufficient for moderate overclocks. To safely step it up a notch you'll need adequate liquid cooling options, like the h100i. Although I'd suggest looking into other premade water cooling units. Do some research and find what seems to suit your preferences best
If you do opt for a budget air cooler though, I'd advise going with the 212+ over the evo as you get relatively the same performance, minus some of the noise