Back before EPA and OSHA their used to be small foundries everywhere. Large
boat yards like Herreshoff also had foundries and made their
hardware on site. In the early '70s had
windlass cast by the Moritz Foundry in Costa Mesa. Cut a foot off the
anchor chain and he cast a
gypsy to match. Really nifty piece of
gear, ratchet and pawl with no springs to break, double handles so you could haul in the
rode relatively fast though it still was all muscle. The windlass wouldn't pass OSHA
inspection but worked a charm for us. Too bad that the Lords in Sacramento and DC shut him down though that was probably going to happen in any case as Mr Moritz was in his 60s and had no one around that looked like they would take on the business.
Anyway, your windlass is probably a creation of one of those small foundries. The geared crank handle allows you to crank continuously which may be a bit faster though the gearing will have a lot to do with that. Can't tell from the pictures how you release the chain, maybe pull the handle so the gears no longer mesh. The Moritz had a band break that worked great so you didn't get runaway chain feeding out. Would see how it works before committing to using it. These old windlasses had some quirks that weren't good for longevity, yours not the windlass.
Brass would probably
work fine for a windlass. It's constant immersion in
salt water below the
water line that eats up the zinc in brass. Just leave the post as is. Hopefully someone knows the
history of the Pioneer foundry.