Pegging a 300 PSI comp. tester seems to be the norm. You have the right idea though, with giving the fresh build a bit of time to improve the ring seal. How many miles on the engine?
Plus, it's even across the board so that is a good sign.
^ Good decision on parking it. If you are worried, you can pop the valve cover and verify the cam timing. You could also check the valves with a bore scope if you are really worried but I'm guessing you are probably fine if the cam timing is good.