3.0csi pistons

Good morning All, I am rebuilding an M30 3.0 CSi fitted to a late 1973 car, the engine block needs to be bored. The first oversize +0.25, C/R 9.5, pistons listed by Wallothnesch are 11251261972, total cost €1749 / $2113 for a set of 6. I can purchase a set of 11251262840 pistions +0.25 C/R...