These are only made by one specific place in Tokyo from what I know. They are also made fresh, and expire quickly. When you get them abroad you often have just 2-3 days to eat them.
There are several independent importers of small quanties the rest of Asia and elsewhere, and the prices go quite high, especially if they manage to get them quickly after they've made.
http://www.amazon.com/Tokyo-Banana-Cake-Ginza-Blanc/dp/B00O0...
These are only made by one specific place in Tokyo from what I know. They are also made fresh, and expire quickly. When you get them abroad you often have just 2-3 days to eat them.
There are several independent importers of small quanties the rest of Asia and elsewhere, and the prices go quite high, especially if they manage to get them quickly after they've made.