What would you give....

I don't see much value there. The tank is questionable, the pump may very well be far beyond economic overhaul.

So far as the tank danger you can EASILY hydrotest a tank yourself with a little effort.

WHAT YOU NEED

The tank and a place to work, go figure?

A water source, fill the tank as full as you can get with water. This means orienting the tank so that the water fill port is at absolute top.

A pressure source and accurate gauge such as a CO2 tank.

AFTER you have COMPLETELY filled the tank with water, hook up CO2 or other pressure source NOT oxygen!!!! !!! !! ! ! ! !! ! !!!!!!!!!!!!

And bring pressure up to tank hydrotest rating. You will have to research to find out what this is. It is going to be WAY over operating pressure, perhaps 1.5X or even 2X operating pressure.

One internet post I saw even used a grease gun head immersed in water.........to use the grease pump to build water pressure for the last pressure build

IF the tank fails the water will prevent a disasterous explosion.

THERE IS NO POSSIBLE WAY you could ever get me to use an old tank like that without a hydrotest