Antique Singer Simanco? treadle cast iron lift spring hinge 1922

Description

I salvaged this lift spring from a period cabinet that held a 1922 Singer Simanco? sewing machine. The rest of the cabinet was beyond restoration.  This item includes only 3 of the screws that held it into the cabinet. The fourth was not there.  It is a very solid cast iron piece. On one of the hinged sides the number 5 is cast into the item.  On the other part of the hinge there is a cast number 2.
I am not an expert on sewing machines. This information is given based on research into antique sewing collector's websites. Please look carefully at the pictures to make sure I have described things accurately.  Ask questions if you think I have not described things correctly.
Thank you for looking.