Have you seen this one? https://github.com/msolajic/c64-uni-cart Dunno about the price but they say the pcb is cheap at least. :D It seems like they have a converter for EF cart to magic desk format but not sure if it’s guaranteed right off the bat to work. Cheers
Just an update for anyone who might be interested in physical cartridge built:
Bought and downloaded gmod2 crt, used cartconv and converted to bin , written this into 512k eprom and used regular Ocean compatible cartridge PCB. Works like a charm.
I expected maybe the game will crash once it comes to hi-score saving, but surprisingly it doesn't. At least so far, I beat 7 monsters and made it to hall of fame with no problems. Of course hi-scores will not survive the reboot and that was the sacrifice I was ready for.
Again thanks for this great party game.