I have a model of the the Southern 6133. It is indeed a car bodied EMD locomotive. Problem is pictures of the real one show it to be a FP7 (Passenger locomotive produce from 1949 to 1953) and my model matches a F3 (Freight locomotive produced from 1945 to 1049). So is life. It is made by Model Power.
Mine, notice the 3 port holes.
The true Southern 6133 (notice 2 Port holes)
Santa Fe F3’s with 3 Port Holes