I agree that is the best route.
If the engine needs to be bored out, replacement pistons are the cheapest route. More compression is a low return on power output.
There are other, MUCH less costly ways to make what you have run and run really well. There's no way in heck I'd spend the dough on different pistons and or boring if it's not needed.
Some of these guys are real good at spending other peoples money. You seem to have bought the bill of goods and kool aid so good luck! I hope you get what you want.