Replacement casement operator

I have a Hurd bow window in this house I just purchased with a malfunctioning operator. The window was manufactured circa 1993 (the house was completed in 1994). The operator (shown in the photo for the left casement) is a single arm. I estimate the window to be about 20" wide. I want to replace the operators on both sides so that they match

That does indeed look like the right hardware. The two sets of three screw holes is certainly consistent with the mounting plate on my unit (not shown in this photo). WI'l need to take some measurements, but from the photo I think the 13 1/2" arm length is also correct. Thanks!