Many thanks, Joseph.
I agree that there ought to be a market out there, although it may have died down, now that the centenary is two years ago. I had great hopes that Bachmann would expand their War Department Light Railway stock and, maybe, add another locomotive or two.
Sadly, I am not in a position to commission something like that. I am sure that I saw a thread some years ago, where a contributor had cast some bodies for these, but I cannot find it now.
Thanks for your help.