SSS Kiwi has the right idea in this thread Bike pistons when found will be lighter stronger and allow much higher revs with less load than most car sourced pistons.

I have used Honda XR500 Pistons in a L series 2.3 litre stroker rally engine and being so light they allowed that engine to rev about a 1000 RPM more than normal L series 2400's as people refer to them as, Most were not actually 2400cc more like 2290cc,Therefore check either Wossner or Wiseco catalogs for diameters but I do not believe they give crown heights in most cases but do give pin sizes so some research could be worthwhile