Today, nobody knows how the i5-7600K will overclock.
For skylake, i5-6600K and i7-6700K run out of safe vcore(1.4v or so) before they run out of thermal limits.
I would expect kaby lake to be more similar than different.
That assumes you have a decent case with a couple of 120mm front intake fans or better, and a decent air cooler with a 120mm fan.
At $35 The cm hyper212 is popular and qualifies.
The mounting system is not so great though.
For a smaller alternative in the same price range, you have the cryorig H7 at 145mm tall.
For a quieter alternative look at the scythe kotetsu.
At a step up in cooling, look at the noctua NH-U12s or NH-U14s. the bigger NH-D15s is not really necessary.
A AIO liquid cooler is no more effective and...