^^^ Yup, if someone has the right butt for that saddle, it's a cool car.
A '65 block wouldn't have a VIN, so if need be, I suppose if there was a good '65 383 block out there, you'd have a back-up.
The reason I questioned whether the Seller meant .060 was, as others have mentioned, I'd expect a sonic test before going that far.
Last guy I used for block machining & recip balancing was Lee Sixt, who will sound familiar to older TF fans.
He sonic-checked before going less than that on a late '70s 440; two I had from that era had fairly significant core shift, and a few holes got sleeved on one of them.