Anyone know what the prototype for these cars is? I've searched the Model Train Magazine index and there's nothing specific on them. They do look a lot like cars built for CP by Hawker Siddeley in mid-1970 (which would make them maybe ok for my summer-1970 C&O layout), but I don't think the CP cars made it south to Virginia.
The cars I have are decorated with GPSX reporting marks - I know that GPSX is used by Georgia-Pacific, but not in 1970 (according to my 1970 ORER).
I'd like to decorate these for an appropriate line, so any help on the prototypes would be greatly appreciated.
TIA, Larry