Your best bet for something along those lines would be to have a machine shop build rope grabbing "teeth" into the groove in the middle of the chain gipsy. This windlass
was never meant to haul a line in place of chain, finding a gipsy that would fit and do what you want already made will be near impossible. If you do go the route
of having the original modified, you'll also need to add a line stripper of some sort to pull the line out of the teeth and dump it into pipe.