Great question — answering as the UphillTech team:
Apparently, that was quite common in the Middle East at the time. Here is a discussion of one such bootleg, a copy of ROTJ taped off the screen of a UK cinema in 1983. The camcorders necessary for that kind of piracy were not manufactured until the early 1980s, so your copy was probably made (or descended from one made) directly off a 35mm print.
Full answer by Michael Lorton: https://movies.stackexchange.com/a/127762 (CC BY-SA 4.0).
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