standard tolerance on a gasoline piston compression height is +/- 0.025mm. so your piston is original spec.

if you want to go for super accuracy, check the height of each piston at top dead center installed. there are tolerances on pistons, rods, crank throw, block etc. you can't measure all of these without a lab so easiest is to build the block and check the pistons are all within about .025 (1 thou) at TDC. if all parts are new you can try swapping pistons and rods around to get a match, or machine them level. it is said that you get a smoother idle from this treatment as well as knowing that when you tune to the limit (of detonation onset mainly) you know that all 4 are giving their best.