I have one of these as well, also picked up from a boot sale years ago 10 p
Mine has DVader on the front
Don't think they have any value as far as selling is concerned though, seen them on ebay With BIN prices but never checked on if they ever sell but nice nostalgia piece
I thought as much to be fair. I wast entirely sure of the age of the thing. The only dates on it are 1977, but it did seem quite expensive for the time, if the cassette box is the original and to be believed.
Back into the box of miscellaneous bits it goes. I might even try to play it first, if I can find a cassette player in the house.