Hi Steve, and welcome to the forum. As for the value of the Jag, that's hard to say. The fact that it has cloth seats tells me that someone has done an amaturish restoration on the car, so for that reason alone I'd be skeptical a bit. (No, they did NOT come with cloth interiors, only connolly leather hides) I would be wondering what else it not original. As soon as you start doing things like that (or putting non-original drive trains in) the value of those cars starts to decrease rapidly in my opinion. To make it right would cost several thousand $$$ and thats if the interior is the only thing wrong. I'd have it looked at locally by someone who knows Jags ta make sure the rest of the car is sound and complete.
Basil