Redwagon32 - That would be consistent with my 5 screw K-22 in bright blue, K258xxx, shipped in 1955. No "B" markings. I had wondered if it had been refinshed, but the metal, fit and logo do not appear to be.

I have a letter request pending, so it will be interesting to see how it left the factory. I put a comment on the request about the finish.