Originally Posted by
CPH-Flyer
There are stores in Tokyo that sell it. I don't know if the have a webshop. It is a generally available product, and not specifically made for JAL.
Technically the ones served onboard are made for JAL as it has the JAL logo on the bottles served onboard just like the cheapest mori izo served by JAL are packaged differently. For the generally available ones, there are different grades of the blue tea. Still plenty of inventory for all 4 grades when I checked just now. Pretty obvious which one is served by JAL
https://online.royalbluetea.com
Looks like there's a store/bar at Roppongi too
https://www.royalbluetea.com/boutique/roppongi/