Replacement crank assembly

Hello! It looks to me like your operator is a match for either our 39-253LB & 39-253RB, or the 39-438B & 39-439B. The only difference between them is the design of the guide at the end of the arm, which I can't make out in your photos. The video below will clarify exactly what you need to look out for.

Regardless of which pair you go with, you'll also want the 39-451 and 39-452 covers.