I often wonder what prototype manufacturers use when they make a model, the porthole door windows certainly point to a specific prototype.
Both of those appear to be from the same mold, but I don't know for sure. The only car like that I have is a K-Line 60' Baggage car I repainted for Seaboard Air Line. Here;s a photo of it on some recently laid track that's yet to be ballasted (or scenery applied):
The doors don't quite match those on the cars Seaboard had and should be replaced, but overall the 60' car looks like the 60 footers Seaboard owned.