Funny thing about folks that really get the collecting bug is that there are variations of the PC marked magazines too, depending on which different ones we're talking about. I have two different .356TSW magazines that came with my 3566 Limited and both are PC marked but quite obviously different from each other.
There are so many things you could be compelled to chase. Matter of fact, I have an extremely rare 4506 magazine that I suspect almost nobody has… it's a magazine with the LAPRAAC emblem on the floorplate and as far as I know, it came with the short run 4506 of the same name. I doubt it was ever sold as an accessory so I believe the one I own was separated from this pistol.
As rare as this is… I also cannot imagine much of a market for it.