Just found a 68 Formula S 383 Cuda. What's it worth?

So I was cruising around my home town and found a 383 formula S cuda in a field that's a solid car. Somebody put fenderwell headers on it but aside from that it's an all original 4 speed car. The guy is asking 13k which I think is a bit steep but for a car with 0 rust that's all there I guess it could be worth it. What was the production number of those cars with the 383? I'll try to get some pics up, just curious if somebody knows a bit about them. I'm not a cuda guy but I like the fastback body style that year. If anyone could shine some light on the rough value of a car that needs resto. All the trim etc is all there.