[Arran]

The car radio based models were definitely a late introduction, I'm not sure how long they were produced but car production was discontinued in January or February of 1942, they must have made quite a few as they keep turning up. They discontinued production in, or around the same time in Canada as well, even though Canada technically entered the war in October of 1939. It's interesting to see the evolution of radio production over the period of the 1940-42 model years, such as how they substituted wood for metal in dial escutcheons, replaced brass knob trim with gold paint, and saved on steel by using sheets of asbestos rather then steel bottom covers on chassis, though some still used steel right up until production ceased. There were also peculiar choices made, like substituting P.M speakers for field coil ones, presumably because nickel was a strategic metal, and random choices in tube sockets suppliers.
We had kind of an interesting mix of war production, ground vehicles were typically Canadian versions of American ones, except for tanks, aircraft were almost all of British design, built in Canadian factories, for the RAF and RCAF, and navy ships were more or less Canadian designed, and Canadian built. As for radio equipment, some was British designed, adapted for Canadian production, some was American, and some was Canadian designed and built. I'm not exactly sure what Philco of Canada was doing at the time, if they were not manufacturing radio equipment it must have been components for same, or perhaps gun parts.
Regards
Arran