Kydex to fit > 400 pistols costs $65, and they offer a drop-leg mount for $30 that allows you (you being a police officer) to move your holster to your thigh so you can still access it after you don armor. Some interesting designs like kydex handcuff mounts, double-pistol mounts, and (believe it or not) kydex holsters that fit a pistol with a spare mag mount on top of it. Not something I'd want, but apparently there are police officers that believe this makes a lot of sense.
https://www.krounds.com/
https://www.krounds.com/
