Maunsell d2653 general saloon coach
20 of these(including brake version) were introduced in 1930s for Continental boat traffic, but could be found in other specialist trains. Useful as not allocated into sets.
Requires bogies, wheels etc and finishing.
HO scale(1/87 3.5mm/ft)
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more info about the Maunsell SR coaches here
https://en.wikipedia.org/wiki/SR_Maunsell_carriage
more 3d printed models from Recreation21 here
http://www.rue-d-etropal.com/3D-printing/3d_printed_designs.htm
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