Perhaps its the provisional offshoot of the Church Army?
Nononononononoooooo... so wrong on so many levels.....
As for JB, didn't he moonlight for Ernest Marples in the late 50s-early 60s?
And the "Russianised" J15 in a later post. Hattons are selling J15s fairly inexpensively, so it might be fun to do a conversion, with a fully detailed guards van containing a huge samovar! Btw, is that supposed to be Lenin hanging onto the r/h side of the smokebox?