Thanks! I've been checking the math on this machine (math is not my strongest suit), and it seems that they would have been able to hoist stone blocks weighing up to two tons, with some effort. So the winch is more powerful than it looks!
Modeling chains is pretty easy in Blender once you get the hang of it. You make a single link, then use modifiers to create an array and bind it to a curve. It just takes some care in setting up the curve.
If you look closely you'll see that the links bend slightly as they follow the curve around the drum. There are ways to prevent this but they involve a few more steps. Not worried about it here -- there's no way it will show in the final rendering.
