Missing Crestline operator

It's hard to say what can work without seeing what was installed originally. Would you happen to have an identical window elsewhere in the house that you can use as reference?

If not, I've done a little detective work and I have a couple ideas. Looking at your photo, it looks like you might have a sash bracket like our 39-548, seen at the back of the sash. If I'm right, you might be able to use our 39-318, 39-221 or the 39-036. These are all compatible with the 39-548 bracket. Look over the dimensions we show for each and see how well they line up with the space available.