Thank you, I have been told that only 6 were made - it sounds quite unlikely, but I haven't seen another.
I have also read elsewhere that a handful were made for the MOD operating in Norway? again - I don't know how true that is.
Its seems to be an oddity and it will be getting restored and used, its in good condition and has been kept very original. There is cab heater and a few modifications to engine to aid cold weather starting.
I have owned it for less than a month, the picture I uploaded was it being delivered