Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

A very nice engine there Jack, thanks for sharing!

Had it been late 40s or early 50s, it wouldn´t have had the riveted boiler or the standalone lamppost.
This leans more towards the mid than the late 1940s, made from leftover pre-war parts, just as soon as Jensen was freed up from their WWII government contract.
Also it should indeed "typically carry a bit of a premium", as casually remarked in the movie, being as rare as it is, when compared to both earlier and later versions.