Hello,
Unfortunately, we could not find a match for your operator with the same rounded body with rear-mounted screws and a 13-1/2" long arm. I suggest taking a look at the 39-406 and 39-407 operators. Note that these operators are front mounted. You would need to use a "nut & bolt" to mount it to your window frame. You could also use the 33-205 thread-nut, which has a thread count of 10-24. Take a look and see if this matches the screws you already have. To install it, I place the nut onto the front of the operator, pressing it in with the help of a vise. Take a look at the suggested hardware and related videos. Thanks for posting.
