1971 Dodge Dart swinger

Hi, I’m trying to find out what my late husbands 1971 Dodge Dart Swinger May possibly be worth. It’s rust free, has original glass (crack free), everything under the hood is original (although it’s seen better days), but he gutted the interior (although I still have everything he took out). I’ve also got a narrowed rear end and a set of drag slicks he had intended for the car but unfortunately passed before he had the chance. I had someone offer me $500 for the car but feel like they are just trying to take advantage of my lack of knowledge of the car. Was wondering if this actually is a fair price or am I right by holding off?

You did the right thing by waiting until you talk to some Mopar guys.
A parts car is worth 500, and I see disassembled cars or no motor and trans going for a lot more than that.