Sceptre makes all right quality monitors. I would expect to pick it up less than $50 though, unless it is flat screen with a great picture.
You can buy them new for as little as $70-80 anymore. Then if you have to factor in shipping etc... Sounds like a sour deal.
I'd pay 40 tops.. Maybe 35. I usually pay people $10 for used 17". Nicer ones I offer them $15. Then I sell them for double / triple the price, depending on the condition.