C&O had a class of 40' steel, Deco end box cars built in 1937. They were numbered 5000 - 5499.
In the mid-1960's "Chessie" era, some went to the B&O, numbered in the 167500-169576 series.
All but seven were off the roster by 1974.
While their time frame runs beyond that of this freight car group, they were in the last decades of it.
The attached photo is of an O scale brass model of a C&O Deco end car imported by Rich Yoder in 2006.