Yes, the best place to source the Tyga parts is from Tyga. They are very good to deal with. I don't know anything about which piston to use, as I've always ran a 300 Tyga kit. Something to do with the stamping. If you do a search on this site, you'll find something on that easily enough, if not, ask Matt or Paul from Tyga. Remember to mention you're a NSR-World supporter for a wee discount