It's the reference roto 30744B

Thanks for reaching out to us! The window operator you have here reminds me of the 39-325 X-Drive Split Arm ROTO Operator. The link arm is connected to the 39-534 ROTO Face Mount Sash Bracket. I am confident this is the replacement you need but be sure to compare to your hardware to confirm.

You'll find the opposite handed versions of these parts below. Both operators are compatible with the 39-232 Roto Folding Crank Handle.

Alternate image for 39-329

Alternate view of the 39-325 operator.