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It was a pretty good scope when it was made and it hasn't gotten worse in all the years that scopes have been getting better. For the shooting that most people will want to do with a fixed 4x it's probably good enough and excellent value for what you'd pay.
At $50 or less, I would buy every one I could find(in the described condition). They are a decent, older scope, if I had to guess a value I would think closer to $100, in that condition, giver or take $20.