You want to run 7500rpm for cheap. Ok, but dont expect it to last forever. The cheap way is SCAT I beams, KB 243 pistons. You will see an increase in compression going to the KB pistons over the Speed Pros you have now.
I don't expect it to last forever, the motor is already at .060 over. My trw's are .025-.030 out of the hole already and cc'ed at 8cc's. The KB's are going to be more outta the block? This is on a stock deck too.