Pretty sure you have a first generation ultradive with a AR 1125 movement. Movement seems to be in pretty good shape. Make sure you put the compressor case back on correctly, you place it on with the zero between the two crowns and the you turn it until the “I” lines up with the little triangle...
By your picture it’s tough to see if the screw is missing. If that was missing the rotor would just fall off and if it was glued if would not spin to wind.. please zoom in, thanks
