The handlebars alone could probably fetch north of $50 on their own. They have become very popular and nice ones where rust is at a minimum might get a lot more than 50.
If I were in the market for a vintage MTB that I wanted to tinker with and maybe turn into an "all-rounder", the Schwinn High Sierra would be a decent candidate.
Hopefully someone similar is in your area looking for a blank canvas with which to create something unique.