Not to compare Intel CPUs to AMDs but I have my FX 6300 oced to 4.4ghz and I am using the same cooler and getting 45c max under a load. You are getting normal temperatures for an overclocked CPU. AS long as your under 70c your super safe
EDIT: Pushing your CPU further wouldn't help much imo, it would cause more damage than it would help. you'll probably only get it to 4.7ghz and it wouldn't be much more of a difference in performance but it will be in temps. It's up to you if you want to go further thoguh