Ok,
Makes more sense.
If you already own the pistons use them. If you are buying pistons buy anything. The Hypereutetics are not a bad way to go with this.
You could buy an alcohol carburetor and run alcohol or E85. Both sell for much less than race gas and will produce power.
I have guys daily driving with BB Chevys using 92 octane and 10.60 -1 compression and we do get on them and run them through the gears. Those are all burning the 92 octane.
What you are wanting to achieve should be easy on the pocket and loads of fun. No high dollar starter necessary. Years ago I ran a 16.85 -1 compressin engine with a beefed factory Chevy 454 Starter with the cast iron nose on it. Now you can buy a late model gear reduction starter from Ac Delco that will spin over a 632.
Ed