Check the holster maker web sites. Many of their products fit more than one model/make
Odin Holsters makes one specific to a Taurus PT111 Millennium Pro
100-450 or so
350$ to 420$
Unless specifically prohibited in the owner's manual, yes.
Neither. Both fulfill their intended function.
The serial number on a Taurus PT111 is typically located on the frame of the firearm, specifically on the right side, just above the trigger guard or on the underside of the slide. It may also be found on the barrel. Always refer to the owner's manual for the exact location, as it can vary slightly between different models.
I recommend target practice, or buying really powerful and accurate guns. If you're wanting to use a less-powerful gun, I recommend using a Millennium Taurus PT111 spring pistol, which shoots at about 180 feet per second, and costs around $15.00. That's the gun I started out with. I've dropped it like 10 times and owned it for 3 years, and it still works like it's brand new. It's not the most accurate gun, but it's a good starter. If you're wanting something more powerful and accurate, I recommend getting something like a DPMS Panther Arms A17 R.I.S electric rifle. This is an automatic M4-based rifle that can shoot at a little over 300 feet per second, and costs around $70.00. Back to the target practice part of my answer, you can find reusable targets at stores where airsoft guns are sold. You can get them from $10.00 to $20.00. Have fun!!