I have what I have always presumed to be an Athearn metal UP
flat car where the stake pockets pop up through openings in the car side.
However, it is a 53'6" length car that someone in the past has nicely
assembled. Is that what you are thinking of, Ben, or did they do
both?
I have a model like that, lettered B&O, and have understood it was a Varney model. Probably Denny knows. <g>