The most I’ve ever seen for a “bumper” in a shop building is small steel blocks about 2 in. wide, 2 in. high, and 3 in. long welded on the top of the rails and that was just on the older tracks in one shop. Even in that shop the newer tracks didn’t have anything at the end.
In a prototype loco shop you don’t want any kind of stops to be over 3 in. high because when, not if, an engine gets into them the pilot will likely get damaged. A very common prototype sight would be flange marks in the floor past the end of the rails.