Wow, that’s crazy. Showed this around at work and the general consensus is that this would be a pre-80s model, maybe mid 70s. It’s a water resistant watch, hence the Seastar branding, and it’s part of the Visodate collection because at the time, having a date complication was something to advertise.
As it says, it’s a Seastar T12 with a Visodate complication.