You'll have to buy the pistons and have them machined to get the correct compression ratio

I just so happen to have a set for sale

Block would need a rebore for the new pistons as you'd have to get a set bigger, always best to go for a rebore if changing pistons i think.

Ive got a spare block too but knew i'd never get round to doing it and since sold the car so no need for the pistons or the turbo i bought now

Scott