I don't know about boosting it up to that high using a stock piston. I don't think your piston and conrod gonna stand up to it for very long. If 6mths is what your after, probably it will.
I'm sure that if you keep the boost to 7psi as what the factory spec on the turbo motors are, it would last a long way.
To lower the compression, I think you will either need to get a custom made head gasket, or to change the piston with lower compression ratio.