I purchased a cheater bar type manifold on squiee Bay and this came with the package. My plan is to set it up DIR style and use for a drysuit inflator hose and octo reg. That way I can dive my Healthways single stage reg here in Alaska and still stay comfy warm.
These pictures didn't turn out too good, but the date on the tank looks to be '43 and it has US GOVT stamped on the neck. It was hydro'd again in 1960 and the valve is a 1959. These were sold in the 1959 catalog as a shallow water training aid. It came with the plastic(vinyl) harness it still wears along with an aqua matic side exhaust reg.
The tank is 18 cu. ft. at 1800psi. So far, I've only pumped it up to 600 psi, but it's been holding it for over a week now.
I am assuming the tanks are war surplus oxygen tanks that were picked up on the cheap by USD.