The coach pictured is an LNER Thompson design, probably a corridor composite as a first class door is depicted. The original design had square cornered windows but due to corrosion problems, these were later replaced with round cornered windows as seen in this picture. Many of these coachers were built by BR post 1948 and it is possible that this one was originally turned out in BR blood and custard livery. I would think that anything after 1949/1950 would be contemporary.