I think that is a great price for what you're getting. I don't think it's a clone as such but a custom recreation.
Using better parts and upgrading to better than stock is nice if you don't have to worry about being correct, like in this instance. If and when I was looking for a 'Cuda (73) this would have been ideal.
Look at what 70 Cuda bodies are going for, in either rolling chassis or drivers, some are reaching $15K+. If you can build a car to that standard including getting a drivetrain with $17K you're doing well. I'm sure prices are dropping as when I was looking a year or so ago this car would have been closer to $40K. Not saying the car is mint but it's definitely no POS. If you want it, make the owner an offer of $28k & play from there......