The gauge is in the $10 range on ebay. The BCs might be salvagebable. Inflate them and submerge in water to find out where they are leaking, inflators and dump valves commonly leak but are easy to repair. If they have internal bladders you can get to, then odds are you can Aquaseal them if they have pin holes. I see a couple of knobs that appear to be CO2 actuators, if the cartriges are missing, air will leak from them. They are easy to plug with a standard 3/8 reg plug......or a new cartrige if you prefer.