Except that I've never seen a prototype orange stripe NH car that didn't have a black roof.
All silver cars ,yes:
But, orange stripe - always with the black, smooth (non-corrugated) roof:
All the WbB, I believe, have silver, corrugated roofs.
I'm not sure about the Railking, but I know that MTH made these cars in their premier line (18" cars) with the correct paint scheme, but with smooth sides and roof.
Jim