Some information

The Japanese DVD

You can get it if you are lucky in an import department. You can also try http://www.ivc-tokyo.co.jp/ (if you understand Japanese ; which is not my case). It is the commercial site of the editor so maybe you will be able to command it. Good luck.
The menus are in Japanese, but it's easy to guess : movie (in French), chapters, text about Grimault (dixit my friend who reads Japanese), choice of subtitles (Japanese or nothing).