A compass that reads like that is a standard nautical compass. Or at least was one no more than 20 years ago. I've been on vanilla 25' cabin cruisers in the past 20 years that have compasses like that. Hell, compasses like that were in cars less than 20 years ago, for crying out loud.
Sure, not familiar to the racers, but they are definitely not some incredibly archaic thing that only a "maritime historian, or antiques expert" would know.