You have to go with similar feature units with that age product.
Usually the money is in the speakers which if not decades old can fetch a little but with all the changes over the years my sons have no interest in a stereo unit today. This is typical and as you can see unless it has some retro look or was a "Mcintosh" brand folk recognize my bet is you'll ask 100+shipping.
I have a casio M560 25CA1 stereo that I have had since 1989. & I'm thinking of selling it. I have Google'd, bing'd it, searched it on ebay and every time no matching results.

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