You may have better luck looking for used winches and just using the drum from the one you find. Used chromed bronze lewmar 30's usually go for around $150. I sold a set for a friend on Ebay for $300. He had upgraded to ST30's.
You might find a bronze or stainless one for less than you can find just a drum.
Also that dreaded Ebay for us bottom feeders, I just found a set of unused Chromed bronze Barient 27-48ST for less than 1/3 the cost of new Lewmars or Harkens.
TO machine, insert new bronze races and finish machine the races to size would cost more than finding a used winch....
Cal 9.2 #19 SilverSwan