Looking for any cracked and ready-for-the-trash 1950's Raleigh soldered-end brake cable sets that might happen to have this pesky, oversized step-down ferrule on it. It might be on '52 and earlier bikes; '53+ seemed to use a much larger ferrule.
This one is a few millimeters bigger than the 1980's Dia-Compe ferrule that looks like it; it fits a fairly large and loose 5 ~ 5.5mm standard ferrule inside it.
-Kurt