A lot of the short shifters on the market will resemble the stock one. Easiest way to determine would be to compare with a stock car.
You may pull the shift boot, take a picture and post it. The top plate covering the ball/cup assembly and the hardware may not look stock. Someone may not be able to identify the brand, but will be able to tell if it is stock or not.
Example of short shifters. Besides the IRP and the Billet Pro Shop shifter, the others have mechanisms that closely resemble the stock one.
https://www.ft86speedfactory.com/dri...ifters-52.html