My take is a little different. I have two M10s with the Uzi magwell conversion. I bought a Beta-C for the Uzi. It is basically a 32 round Uzi mag that is held onto the Beta drum with a plastic collar. I would think that it would not be very hard to 3D print a collar, like that of the Uzi, for the 30 round Z-mag. It would not be very hard, to buy a Glock
https://betaco.com/c-mag-systems/9mm/9mm-glock/ Beta-C drum, which looks like it also uses a collar on a 33 round Glock mag for the tower. I suggest the Glock Beta-C because it is a double stack, single feed like the Z-mag. So the dummy rounds in the Glock feed tower would be similar to what the Z-mag would need.
"chili" is right that there is a small market for a drum that would feed in the grip. But for those that already owned 9mm Beta-C drums, a retrofit collar to use a Z-mag, I would think would have some interest.
Beta-C drums suck to use in a semi. Half of the Beta-C mags I own, I bought from semi auto owners that used them a couple of times and sold them at a discount. I think that the 31 series of Lage uppers scratches that itch for many Mac style RR owners. Personally I don't care for the 31. I like the Beta-C mags. I would be interested in a couple of Z-mag collars. But I have too many projects that I have a vested interest in finishing. I do find it interesting that Beta-C mags really shine in full auto, yet the most prolific registered receiver machinegun in the transferable registry doesn't have a 9mm Beta-C for it. There are no transferable Glocks but BETACO has a Beta-C model for it.
Scott