I am in Japan as well and decided due to current yen rate, and still having to wait to get the quad 27' that i was just going to order it.
to answer your question though, you CAN buy one here with NO problems as all. The plugs are the same, the power is universal, and the english language is programmed in you just have to change it in preferences.
Hope that helped. IMO you should just order one. If you are military, check out a company called "APO Box" not only do they deliver to us out here, but you also get a apple discount through them (google apo box apple store).
anyways hope that all helps ya!