Not sure what will replace my operator

The 39-031 and 39-032 are the first things to come to mind. Can you specify why these won't work?

Have you looked at the pages I linked you to in my first response? We have detailed information, dimensions, and pictures that you can go over to confirm if they match. For the two piece arm, you don't measure the whole thing, just the link. Again, you can go over all the dimensions we show for the 39-031 and 39-032 on their store pages. The dimensions we show are the most important ones.