Definitely a original car should be worth more.
I'm not the guy who says what other people's cars are worth. I'm the guy who decides how much I would pay for a car.
Last spring I bought a 66 440 4 speed sport fury . The guy was asking 14 I offered 12 grand and he didnt take long to say OK. The car was on kijiji. He had a flurry of offers under 10 grand. This car appraised at 21,500 it's way more rare than a 65 polara 440 .
Did you inspect the polara? Is it a original 4 speed car?
My 880 conversion would fool almost everyone