Those changes aren't impossible but you'll probably spend more $, time and energy than it's worth. I'd suggest selling the PGP and looking for a Piranha SB (or LB if you want a longer barrel). Same platform but factory build with your 2 requirements. You should come out about even $ wise that way. Or... for about the same price as modding the PGP you can probably just pick up one of the guns listed. P68 magnum is another one you can pick up for $80 or less and might fit what you're looking for.