Cant find right hand window Operator

This is from a house that was build in 1925. The arm that comes out of the box does not protrude out of the box when fully close which makes it difficult to identify the correct window operator. From what I could measure, the arm that is connected by the screw is about 2 3/8 in length.The space between the two bottom hole is about 1 3/16 and the top to bottom height is about 5 1/4.

Ive added two more photos so I can show the inner arm and how far it pokes out of the box and also the shape