No, they're real. I think mine was made by Sears, and I think they only made them for two or three years. Wire recorders were problematic. The wire would break, and there was no easy way to splice them.
Germans invented "tape" recording, and it was so much better than wire recording, everyone went to that.
Mine came with one intact spool of recording wire. I've never tried to load it because I don't want to damage it. The record player and the radio work though, and I assume the wire recorder and playback works, but I haven't tried it.
I also have a "portable" television set from the 1950s sitting in my office, and I would like to get an even older one from the 1940s. Ever so often I cruise Ebay looking at them, but I really don't have time to devote to this sort of novelty stuff right now.
But I just thought I would say I share your interest in old things.
The only ones I saw were on episodes of Hogan’s Heroes.
Must have been American. The Germans were using tape at that time. :)