I haven't heard of any G10 revolver grips.
I don't know what exactly they're made of, but Precision Gun Specialties makes some good synthetic grips for J frames. I have a set for my 642, but I haven't had a chance to shoot with them yet. I have a set for my 65 (K frame) and I really like them. They're also not that expensive, usually $18-$20, so it shouldn't break the bank if you want to try them. Brownells usually has them in stock.