1 361 486 L, 1 351 483 RGR Anderson crank

It's tough to make out what you have from this photo. All I can say for sure is that this is an Andersen brand operator. I would start by looking at our 39-264 link arm operator or our 39-331 straight arm operator. One of these may be a match, but you should remove the old one to confirm which is best.

Depending on when your window was made, you might also need the 39-362 sill adapter plate. This allows modern  operators to install in windows made between 1995 and 1998.