Casement Window operator replacement

A handy person from Porter, Maine says:
June 21, 2017
I'm looking to replace casement window operators for casement windows installed in late 50's. They are operated with square key stock bent into a crank. with a rotating metal spinner for fingers to rotate the crank. The operator has an arm about 12" long that slips into the track mounted horizontally across the sash near the bottom, on the inside of the window. There is a half round cut-out to connect the operator arm to the track on the window. The operator body is mounted to the window sill with two vertical wood screws on each end. The operator gear box are are 2" long (not including the mounting tabs)by 1& 1/4"wide", thickness does not matter. I don't find any markings on existing units.
The units are flat sides, top and bottom with tabs extending on each end with two screw holes each for mounting.

I need thirteen Operators

Charles E
A handy person from Porter, Maine says:
June 22, 2017
I'm having issues with my computer getting photos to export. I'm sending photos by US mail to you.
Profile picture of Dave Sr.
Dave Sr. from SWISCO responded:
June 22, 2017
Charles, this is just a shot in the dark, but take a look at the 39-268 operator. This operator was used on early wood casement windows. See if this is the part you are looking for, and let us know.
Wood Casement Window Operator
Wood Casement Window Operator
39-268
$25.12
Anatomy of a casement window
Anatomy of a casement window
VIDEO
WATCH >
How to install the 39-268 wood window crank operator
How to install the 39-268 wood window crank operator
GUIDE
READ >
How to identify casement and awning operators
How to identify casement and awning operators
GUIDE
READ >
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)
Current wait time is 3-4 business days
We promise that one of our experts will personally get back to you as soon as they are able. Thank you very much for your patience and understanding. If your inquiry is time-sensitive, please feel free to reach us at (888) 991-1929 or at help@swisco.com.