Well stock SVO pistons are tough to find because they are bulletproof (made by TRW), but no longer available. You'd probably pay as much for stock SVO's as you would for aftermarket pistons which you could have made with higher compression (what you'll need to get any power from an N/A 2.3).

And the NA and turbo rods are the same, and turbo guys make 400hp from stock rods. So you don't need aftermarket rods.