From Centerline's carb rejetting thread:
"... I found shims that will work nicely for raising the needle on the Teikei carbs. They are available from an industrial supply house called McMaster/Carr. They can be found at
www.mcmaster.com. The shims I purchased were part #99040A300. They are available in packs of 25 washers. You can order them in varying thicknesses from .001" to .016". I ordered mine in a .010" thickness. The washers are made from 18-8 stainless steel. They are .125" I.D and .187" O.D. I paid $7.81 plus shipping for the pack of 25 washers. They fit nicely with no binding."
Jets are available from your local Yamaha dealer or any of the online vendors that sell OEM parts:
Satdium Yamaha
boats.net
Ron Ayres
Bike Bandit
... and a few others.
Part numbers for some of the jets are near the end of Qwerty's Carb Tuning thread:
http://tw200forum.com/index.php?/topic/647-carb-tuning/
jb