I wonder if the box full came from the huge auction of old army stores at Bandiana a couple of years ago?
Very nice find Chris!
Just picked up a 1944 pattern UK one dated 1953, same maker, but in a cotton duck pouch (pics in the 44pat thread).
Just cleaned a little grease off and got a surprise.......
The bag markings are almost faded away, but "wood" is visible.... Whether that is the manufacturer or the nomenclature, I'm not sure.
The saw itself is marked "DITTON, USA, 1944, /I\, ". Geuss it was left over lend lease stock.