I believe the hub was also used on late 1930s through 1950s Schwinn Superiors. It is way more than a paper weight and will return many $$$ on your investment from the barn. It would be great if you had the matching front. But what you have is in great shape. Below is the link for the 1939-40 Catalog page.
http://http://www.trfindley.com/flsc...0/1939_10.html