On Monday, February 13, 2017 at 6:44:06 PM UTC-8, wrote:
No markings. Were these manufactured with some standard rear axel or a variety of parts? Most look like a GM 48 inches wide, between brake drums.

Join Yahoo WinchDesign group and ask. As far as I know, they were built with whatever happened to be available at the time. Might be cheaper to replace the entire axle with, say, a Ford 9 inch or something newer, for which parts will be more readily available.

Marc