I would tell shop do a piston swap to get compression up. If you have no budget for piston swap then run a .028 head gasket and when you get more funds later you can upgrade it then.
I would not deck the block with existing pistons cause then intake has to be machined by the time you pay for that could have probably bought the pistons.
Sure a stroker and big roller cam would be great but not sure why shop insist on going that route if its outside your budget when a basic piston swap would make it a great engine?
Since seller lied about pistons makes you wonder what else they lied about?