No clue. If you've already tried places like redwolf, WCG, and stuff like that maybe you can get it direct from the factory.
I know they don't like selling parts to the public though (probably like a payroll shipping thing that's more work than it's worth) so maybe you have to go ask someone who lives in Japan.
ಠ_ಠLess QQ more Pew Pew
READY TO >> RACE