I'm thinking that is a refurbished 66, possibly done in the 1930s or 1940s. When the companies did refurbish and add motors and lights to them, they were remove all indication that they were a singer. Many have survived with the plaque like is on the arm and the original badge on the pillar. I'm thinking that it could have been either a treadle or came with electric motor. It would have been an upgrade. The light does look like it is a Simanco numbered light, but couldn't tell about the motor. Although even if it had been an original Singer motor, it could have been switched out in the last 90 or so years.
I was thinking Miriam had another thread about refurbished machine that were done later, but unable to find it. Here is one of the thread she did about them -
refurbished or electrified sewing machines from 1930s and 1940s It seems that the refurbished machines from the 1950s would sometimes include a few Revco items.
Janey - Neat people never make the exciting discoveries I do.
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