Hi,
first of all, I'd say you're one luck son of a gun.
You found a 65 ss and not just that, a 2 door on top on top of it.
The owner is not just getting the car done, he is importing parts from abroad and getting the car ready for the buyer.
what else do you need bro? I mean it's way beyond a fair offer if the car is freshly painted with rust free body under the seats. The V8 alone is enough to rip you off. Consider yourself lucky you've found a ready made deal.
I'd say bargain as much as you can and done the deal. Don't let it go as 2 doors are not only hard to come by but are rear beauties in the land of jap crap. American cars are the real deal. If you're not interested, do let me know as I have been trying my *** off to find an impala.