250-500cc NEED HELP - 250 to 300 big bore kit or 300 cylinder and head!

Hey guys I recently brought a 2004 wr 250 with a sleeved barrel to suit 300 size piston. THe bike was great however shortly after purchase developed issues. Now I want to get the correct factory 300 parts to suit however they are just no existant in Australia. Therefore im hoping someone in the states can put me onto them and I can have them shipped over.

I need either:

The 250 - 300 Factory Kit (8000H0915) this includes piston and rings, cylinder with powervalve assembly and head

or

300 Cylinder (8000H0698)
300 Head (8000H0673)
Power Valve (8000H0675)
Booster Valves (8000H0676)
Reuse rest of powervalve from 250 as its the same (the linkages ect)

I can buy piston and rings and gaskets in Australia.

Im currently in contact with halls and hope to hear back from them shortly regarding availability. Just wondering if theres anywhere else in the states I should contact or wether anyone has any of this stuff?

I have a stock 300 head if you need it.

what did you end up doing?