I was trying to find Joe's Hother besides his avatar and happened across another with same decals badged "Crown" at
My new-to-me vintage machine, made in post-war Japan I also noticed your Sinclair badge has Seawol Sewing Supplies on yours and the Crown. I have an unbadged 15 clone (I looked really hard to find a name on the arm) that you had to take the motor off to find out that it was made in Japan. It has a label stating Seawol USA on the front under lip of my machine. I did some research and IIRC it was in about 1954 that a lot of machines were coming into the USA without prominent display of the country of origin. There were some suits/judgements against some of these companies/importers of which Seawol was one of them. My Seawol has gold decals.
Janey - Neat people never make the exciting discoveries I do.