You folks are already teaching me a great deal! Love that cabinet and wonder if it was ever a treadle. Here's why I ask.
Checked out that White set of treadle irons that I mentioned earlier. It was also a gift of sorts (Centralia freecycle) from an enabling friend. It's a Frankentreadle! Right side iron is a White, who knows that the left side is nor the pedal. There are no identifying marks and zero holes for mounting any cross brace. The distance between irons is 18 1/2" so I can't even adapt the top to the Singer irons without removing drawers.
It is essential to have the base solid. So frustrated. I think I'll have to back up and re-think. There's no needle printed on the front slide plate. It's serial # is 766486.
I know it was purchased new as a treadle because it was from the Kansas City Sewing Machine Co.. They routinely "updated" treadle heads to make them appear new when the motor was mounted. That means they slathered the poor thing with brown crinkle paint, which is flaking off in small chunks. I rebuilt the motor to use as an electric. It's mounted and ready. I just love to treadle when quilting because of the complete control.
That $60 machine is looking better and better. Perhaps could retro fit treadle components inside. Thoughts?