CADOJ has now clarified (somewhat) what they consider permanent: epoxy and rivet.
http://crpa.org/doj-proposed-regs-la...ity-magazines/
There are Glock mag blocks but the ones I've seen epoxy to the follower, not the baseplate. I don't know if those would be deemed worthy with a riveted baseplate or if we need to wait for "magpul-style" floorplate-connected blocks. Either way it seems like blocking G19 mags is a viable alternative to factory 10-rounders.
[QUOTE=GardoneVT;537299]