The 254 / 4U frame is unique to those 2 locos, not used for anything else.
Although the 250 series of "tinplate" electrics are far from "scale", perhaps the Olympian Bi-polar or St Paul style electric that the 254 / 4U electrics were designed after is the answer.
The real Bi-polar had a cab that extended the length of the frame or chassis with no porches on the ends for railings or flag-holders. The 254 / 4U also has a cab that extends near the entire length of the frame, so no flag-holders.