Do you know of any examples of these gears being used in vintage conventional saltwater reels?
John, back in "the day," a conventional saltwater reel was just something big enough to be considered usable for larger, stronger saltwater fish. It took a long time before folks started making the huge trolling reels you're probably referring to. Anyway, W.H. Atkinson patented an amazing reel in 1891. It had planetary gears, a 2-speed transmission, and a drum brake. The transmission was provided to "increase power" when needed, a feature you would need more often for saltwater. Atkinson ran a business for many years making a variety of metal products, and later, auto parts. I can't imagine that he didn't attempt to make and market his reel, knowing that this was his second reel patent. The folks who collect the monster reels are in a better position to answer your question with regard to the later monsters.
Planetary gearing
per se had been in use for two millennia before your reel was made; Leonardo drew them, and lots of machines employed them. Reelmakers often seem to be slow on the technological uptake.
Don, a Geneva movement is used to
produce intermittent motion.