55C = 131F...so if you are wanting you stay within that ~30C range of 100F, you can likely do with about anything, including a good air cooler. However, load temps are dependent upon the voltage it takes to reach your stable overclock goal, so make sure you keep this in mind. Also, you can't cool lower than ambient room temperature with an air cooler or normal watercooling...just FYI.
I don't want you to have expectations higher than what is realistically possible. I have a full watercooling loop and my room temps are around 23-24C ambient right now...74F or so...maybe a bit cooler. My CPU is OC from 2.4ghz to 3.6ghz and at 100% load on Intel Burn test, it can hit 55C, easily, but my water temps are within 5-8C delta of ambient room temp. You are talking about a summer room temperature ambient that is ~10C+ (or 25F+) greater than my winter ambient and wanting to keep your OC chip as cool, or cooler. (This also depends on AMD architecture and OC ability, which I am not as familiar with). Just trying to give you some realistic expectations.