Pete,
I certainly am no expert on these "reproduction" Lugers
, but I think you may be using criteria that are too exacting for analysis of this type of marking. The markings were hand struck. The force of the blow, the tilt of the die and probably a few other factors produced variations in markings, even those created just minutes apart. There may have been a jig to hold the part and the dies for marking, but not necessarily as precisely as those used for manufacturing production. I think the marking of magazines may have been an arsenal or armorers function and not the actual manufacturer of the magazine. Perhaps someone who knows what they are talking about can jump in here and educate me.