If they are in good shape and at least "II's" $300.00 or so would be a good price. The current model "III's" run retail about $1600.00 a pair. I like the Heresy but they really need a sub to get that bottom octave. If all you listened to was Classic Rock and Country you'd probably be alright. They are certainly an improvement over your typical Cerwin Vega in my opinion. Another very good Klipsch vintage model are the Forte.

Carver gear isn't much on current but they always have high power rating so there isn't a need to limit yourself to high efficient speakers. For the price it would be hard to beat the Heresy though. Sometimes you can find nice bookshelf in that price range.

Welcome to AR, BTW