After having it in my possession I am comfortable in ruling out "camera part" which was my original guess over a year ago. Unless it was a part to a play camera and had no function other than to pretend.
When a number is centered in front of the pointer then a point of the sprocket is centered straight across from the number.
I believe that the wheel was designed to be advanced by using a finger to move the wheel. The distance between the points is 9/16" Way too small for a frame of film.
The numbered wheel is held on by a single rivet in the center as stated earlier there is no post for the wheel only the rivet.
I am fairly sure the wheel was meant to be advanced by hand until the stop prevents it from going past 14. The stop prevents the small number 15 from lining up with the pointer. Then the wheel must be rotated in reverse by hand until it hits the stop. when that happens the pointer now lines up with the small number 15 then one move starts it back at 1 again.
Also the little raised tab stop does not look like anything has ever been attached to it.
It's only function being a stop.
Buddy~
BCH you posted while I was writing this. The wheel moves freely with nothing to hold the wheel on a number. Which leads me to believe that the wheel must have been meant to be placed horizontally.