Hyper 212 is perfectly fine for overclocking. My 2500k @ 4.6ghz is still just fine, and I just built my brother a 7600k with a Hyper 212. We are in the process of overclocking it, but so far (as expected) no issues from using this air cooler. You only need a closed loop system if you are going for the look. IMO, even though I have an H115 on my 6700k, closed loop systems are over rated and only eye candy.
I would also get some GSkill 3200 RAM instead of that 2666 corsair.
If you go with a 7600k instead of the 8600k, you will save money and get a higher overclock with cooler temps. More cores = more heat.
Please for the love of all that is holy buy a gold certified PSU.