Wright casement window operator 07900

Can you please help me find the above pictured window operator/crank. As you can see (picture #3) it is mounted under a threshold in the window frame. Picture #4 is taken from the outside of the window. The front inside measurement is 3 3/4 inches the back which is under the threshold is 4 inches. The holes closest to the inside are 1 1/2 inches apart and the outside holes are 3 inches apart. Main arm is 5 1/4 and the second arm is 4 inches long. Can you please help me.

Thank you
Frank