Thanks, Jim! What I can say is that the frame appears to be the same material as used on the little Leonard bimetal shown in the pics above and I thought those were made from NS and bronze, but I guess it might be brass. Old brass takes on about the same patina, but I want to pursue this and try to figure out what it is...just didn't act or polish up like brass, MHO.
The inside of that bearing cap has a "teat" for adjusting the spool, shown here:
does this qualify under the VH patent??