I gave up on 13.1 as I have found py3.8game.tcz in 14.x/aarch64 repository.
So I moved to 14.1/64, but this extension didnt work (was build against different version of SDL than the ones included in repository).
Finally I built the extension from source against the right SDL, and fixed py3.8game.tcz.dep content, did my best. If there's anything I could improve, please let me know.
The file is to big to attach here, so I'll submit the extension via email.