Purchased from an old line Honda dealer who stocked lots of OEM and high quality replacement parts in the heyday of Japanese imports but is now closed. NOS Items may have shelf wear, metal items may have slight corrosion, but pictures taken from all angles and you can ask questions about condition before purchase.
The dealer supported the Cincinnati Police Department fleet of motorcycles in the 1970's. I believe this to be a Honda CB750 gas tank that they used, but no guarantee. look at the dimension pictures to make certain this will fit your need. It has two small shallow dents one on each side towards the back pointed out in the pictures. the inside of the tank is shiny clean no rust visible underneath. The hinge cap works great, and it has a very trick chain system that secures the cap from loss.