Casement operator and frame

Hello, Pete. I see what you mean. That damage to the screw holes in the window frame is an annoying job, though not impossible. Hopefully you'll be able to patch it.

As for the operator, we actually carry a ton of different sizes that may replace this. I'm not sure how long the arm is but see our 39-139 (9-1/2") and 39-142 (11") to start. We have other styles, too, so if yours is different please don't hesitate to reach out. Also note that both have a thin metal disc at the end of the arm by way of track slider. You may want to double check to ensure that yours is the same.

Dimensions for 39-139

Dimensions for 39-142

Great! I'm glad that these parts look promising. Concerning the best way to determine handing, in this case you want to go by the position of the handle relative to the base. So in the case of your photos, the handle is on the left side of the base, which would make it our 39-139. If the handle is on the right side, you want our 39-138.

Every company, contractor, and home owner you'll talk to has their own way of determining left from right. Some define it from the outside looking in, some define it from the inside looking out, others still define it from which side of the window the operator sits on, or even what direction the window opens. There is unfortunately no industry standard.

That's a huge headache, so over the years we've learned to just use the part itself as a reference. What side the handle is on, what direction the arm faces when it's "neutral," and so on. Terminology changes from region to region, but the hard facts never lie.