I used to know a few people that carried them. Swivels, clam shells, single snap, etc. The old duffers that used to carry these have long since retired. The last two I knew of retired about 15 years ago and even they no longer carried those holsters because department regs changed more than 20 years ago. I suspect that unless you go way out of your way to look for one at a gun show or online, you're not going to find one. I seriously doubt the security guard had such a holster unless he was very old school and not at all concerned with weapon security. Even if, for some reason, he had one, it doesn't change the facts and the legal nothingness.