This seems to be a deluxe model with deep cut checkering and a significant raised three dimensional duck in both sides of the receiver
Anyone ever see a Winchester 96 with a duck on it? No. But I once saw a Remington 870 with a chocolate Lab sitting on it ....until I yelled at her. She was such a goofball, but boy could she find ducks. I still miss her, ten years later.
The 96 was the value brand version of the 101, plain wood, coarser checkering, and dead plain receiver (no engraving at all). Do all the numbers match? If not, put together gun, if so I'd lean toward something that was upgraded aftermarket.