i would splurge a bit on a new cooler, even if the stock one holds it's own in the heat department, AMD stock coolers are not nice on the ears and it will sound like a mouse vacuuming your case on turbo
you won't have to spend much to get that.
as for GPU we'd need to know which one, but to be honest with stock numbers so high, you probably have something newer, both the nvidia & amd camps OC OK and you are probably safe at that OC, just run the afterburner tests from MSI (Kombuster) to see if it gets too hot.