Cabinet condition may also speak about driver condition. Typically would suggest $100-200/pr. tops since the LE14 woofer surround (yellow) will have fully stiffened solid by now. Any cosmetic or physical damage to the woofer cones will degrade the value further. Also, damage to the fretwork grille is virtually unrepairable.
Despite cabinets being beat up, unless veneer is chipped or missing, or severely gouged, scratches can be cleaned up and many times JBL cabinets can be cleaned up pretty well. However, we won't tell the sellers, will we?
The woofers are worth more as is since collectors value that sort of thing. If you want to use the woofers, either soften surrounds with DOT3 brake fluid (with a steady hand - read up threads here and Lansing Heritage for tips) or have them replaced with correctly fitting JBL type foam surrounds.
The tweeters (LE20) are nothing particularly special but may garner some $$ as well as the crossover if you're parting them out.
However, the system can make a good EWave candidate.