Here is a vintage Selmer "Classic" model soprano mouthpiece. This mouthpiece measures .053" on my gauge.
These fantastic mouthpieces have been used by so many great musicians from Marcel Mule to John Coltrane. The squeeze chamber and modest rollover baffle really was avant-garde in the world of soprano design which had been very large chambered up until this point.
As shown in the photos, there was a small amount of facing and tip work that was very conservative. It includes the original slide on cap and ligature.