2-300 for the block makes sense. everything else is irrelevant, your going to throw the heads away and buy aluminum, they are cheap in todays market and not worth rebuilding cast iron. same thing with rods, buy good aftermarket h beams and be done. pistons, same thing, buy good aftermarket. now crank is where its funny. if its cast, buy a stoker kit and be done, if its forged, sell it and buy a stoker kit and be done.

without knowing what your plans are for the engine, hard to give any more advice.