my 350Z A/T in trouble, after 3000 km milage I've finished all friction plates and separator steel plates in my A/T gearbox.

Buddies from Japan, told me that I can order plates but only inside new gearbox, is it true? May be anybody already solved the problem and found the place where frictions sold out separately?

Or may be somebody knows, where to find special perfomance plates for this car?