I have been involved in firearms for MANY years.
Reading the forums, there seems to be a group of people who believe that they understand how things are done, (especially at Smith and Wesson).
A number of years ago, I was responsible for placing an order for a re-arm of our police department.
After getting some sample pistols, we decided to purchase model 4566 pistols.
First, most police pistols are NOT engraved with the departments name or insignia.
Second, the pistols I spec'ed were ordered with arched grips (as opposed to the standard flat back strap).
The pistols were to be supplied with 4 additional magazines from the factory.
The pistols were to be supplied with Tritium night sights.
Now, the kicker.....
The pistols were to all be sighted to Point of aim=point of impact at 25 yards with Winchester Ranger Talon 230 grain ammunition.
The ammunition had to be specified, as many ammo's and weights impact differently.
What it comes down to is... virtually anything was possible on a special order from an L.E. Agency.
So, just because something or combination of things is unusual... It could still very well be a department ordered pistol directly from S&W.