In all honesty, I seriously doubt they'd go to the trouble of digging up whatever records they had - if any - and wasting time doing so (just so someone on the other side of the world could mod their car) for no monetary gain. I know that sounds a little harsh, but look at it from their point of veiw.
On the other hand, if you had your car there in Japan, and were willing to pay them to tune your car again (and maybe source a part or two) I'm sure they'd be happy to oblige.
That said, of course you can try, but then you'd need someone who could understand... Japan.. ese... aaah