Very cool retro ‘mid century modern’ speaker, looks great on the bench! In my young audio days, my mentor had a pair of European speakers from that vintage that had single full-range drivers. I was always impressed by the fidelity of those speakers despite not having tweeters, crossover or anything more sophisticated. I think the drivers were either Phillips or Norelco.
Neat find! I restored a Telefunken Allegro 5183w receiver many years ago for a good friend. It came with a pair of those speakers to provide stereo separation. I'm guessing that Telefunken probably sold the speakers as add-ons for other models that were stereo.