I plan to release new cartridges when the version 2 is ready. I hope that it will be in 2021, but can't promise anything. We are still in very early stages of this version.
I do not plan to produce more cartridges of the version 1.
In the meantime you are free to download the game and put it in an everdrive, or even produce your own cartridge. I know that it is not the same thing as an "official" cartridge, I am sorry for not being able to bring better news.