This is a subject where much is unknown … and very likely to remain that way.
Demand for 7,9 chargers during the 1914-18 War was prodigious and I have a feeling that much of the production was sub-contracted to local metal-working shops. Pre-1914 Germany was one of the main suppliers of pressed steel toys, often clockwork driven … all skills that transferred neatly into a war-time economy … at the time Britain imported a lot of its clock-mechanisms from Europe, especially Germany … when war broke out we were woefully bereft of companies able to make all sorts of fuzes as a consequence.
If a list of these contractors names and the marks they used ever existed then it’s either still buried or has been lost … to the original users of these things it would be incredible that they’re now the subject of collectors interest. I have a reasonable collection of these chargers, but this one I don’t have … and the only mention I’ve ever seen of it is a small sketch in a “wants list” from Stephen L Fuller, a collector in California … the list is dated December 1978.
The top two are indeed Czech, for a short while after 1945 the country had a relatively benign government that traded freely with much of the world … Israel was the beneficiary of much military equipment bought from there in the early years if its existence. Sadly that openess wasn’t to last and Moscow clamped the dead-hand of Communist rule there … as it had in the other benighted countries that fell under its purview. You’ll find these Czech chargers dated 1949, 50 and 51.
Most are bright nickle plated but the one above has only two lugs per side and a phosphate coating … which isn’t often seen.
Unmarked bright-plated 7,9x57 chargers are very common … a lot came from Yugoslavia but FN in Belgium was another common source, they only very rarely marked things like chargers.