How many RPM can stock GX340 handle?

What I need is a billet flywheel that works with both the factory electric and recoil starters, and charge coils.
Does any such animal exist?
I've searched for a flywheel like that for my 420 predator and found nothing with magnets for the charge coil. I think you can bolt a starter ring onto a recoil billet flywheel, but don't quote me on that.