Just sent a query to my brother in Tokyo.
EDIT: He wasn't positive, but there are apparently some places that specialize in getting various Asian media products. One he mentioned was
http://www.play-asia.com/ but for music it looks like they're more into anime soundtracks, j-pop, game music, and the like. I'm assuming you're in search of some classical piece, but I wouldn't be surprised if that wasn't your quest, Paul.
Perhaps if this site doesn't have it, the kind of site it is might give you a lead.
(If you want, I'll pass along the specific title along with where you did find it, and he might be able to do a more thorough search via Japanese search engines and sites.)