http://www.importbuilders.com/pistons.html
There's a piston listing of off the shelf pistons that importbuilders sells. Your compression ratio will be different because the compressions listed are with a VTEC head. 11.5:1 isn't really high, that's a decent NA compression ratio...you could run it on pump gas no problem. You can always order a piston with whatever compression ratio you want...they can make it.
__________________
2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
Team B.O.B.® - Ballaz on a Budget