Sorry to see you go through this headache! In the very distant future I definitely plan on getting a supercharger and xpipe as well. Emissions is a huge concern for me though and I definitely wouldn't want to go through half of what you're going through right now just to get a stupid sticker.
Doesn't MA allow all cars 2001+ to fail one readiness check? If your car is only throwing o2 readiness wouldn't it still pass anyways?