A contractor from New jersey says:
April 29, 2016
Gear mechanism nuprimewindow
Tom from SWISCO responded:
May 2, 2016
Thanks for posting. This part is known as an operator. I'm confident we can replace this, but we will need a bit more information before we can recommend anything. Please open the window as wide as you can and show us a top-down picture of the arm(s) attached to the gear base shown in your current picture. That will help us come up with a match.