Good luck been working on this for over a year and have been in contact with JAL and the company that makes it. The company that makes it gets messages daily.
I "had to"
hang out with a JAL flight attendant to get a few bottles lol, as a present for a friend.
I also learned you can special order it thru the duty free at the airport in Japan it works out to something crazy like $48cnd but couldnt figure out if it was for a 1L or 6x1L.
The japanese store on Robson near ebisu gets a simliar drink from time to time but it sells out extreamly quick and they never know when their supplier will drop it off.