Not so vintage at all. This is a power d-sub. Used in industrial appliances for example. I have seen them used in traffic signs, fire alarm systems and more.
They can carry a data signal and power UP to 30 amps. For example to control a motor, or to power the boards on the other end. You can find them on digikey if you want to find this type and geht the specs. If you have trouble finding them, look for the NOR1344-ND