I need the '64/'65 tank with the monza style cap.
I'm pretty sure I have one, and probably two, of the tanks you're looking for. However, they're sitting on a shelf just below the 13 ft. ceiling of my garage.
So, make me an offer I can't refuse via a PM, that takes into account the headache of dragging a ladder into the garage, maneuvering it past everything in the way between the door and the far corner of the garage, and getting them down to photograph to confirm they're the correct tanks. If they turn out to be correct, whichever of the two you choose will be yours. It's best to assume they'll have small chips and dings, and need to be repainted. I hate haggling so if I like your offer, it's yours, but if it's too low, it's not.
Both of them have been stored since before the first ethanol ever was distilled so there won't be any blistering and bubbling, and I'll personally guarantee the insides won't have rusted. If they turn out to be from the wrong year, or you don't like what you see, you can withdraw your one-and-only offer and the tanks will go back up on the shelf.