Split arm casement operator

Hi,

I'm looking for a split arm casement operator. I do not know the window manufacturer. I believe this is a right hand casement mounted closure. But it is the closure for the window that is on the left side of the bay window. The only markings are the numbers 30866 on the arm and made in USA on bottom of the mount bracket right where the gears meet. The closure is 5&1/2 inches long and the mount screws are 5 inches apart.
Thank you in advance for your time.