Broken lock handle on casement window

I'm hoping to order a replacement lock handle (and associated lock mechanism) for a casement window. My daughter broke the handle by pulling on it too hard. After looking at your parts, I believe you're the manufacturer of my window, but don't know for sure. I've attached pictures of the window and parts for you to look at. Could you please confirm that you are in fact the manufacturer, and let me know what replacement part needs to be ordered.

As you can see from the picture of the broken handle, that's the component (as well as the internal mechanism) that I need replaced. It looks like that handle, as well as the small "box" that it connects to that is on the indoor side of the window can be unscrewed and removed/replaced. The vertical metal bar that slides up and down to lock/unlock is still intact (I included a picture of that to help you confirm what type of window I have).

I came upon your site by doing a Google Search for C-C45-96x60 -- the code written on a label on the inside of the window. That brought me to another post by another customer.

Thanks. I'll look at that and check the measurements.

I have same type window with a broken lock handle.

My problem is that I have noticed that you have to open the window to removed the screws that hold the lock mechanism that you replace with the handle.

My window is closed and locked. It is broken inside the handle is still intact but does nothing.

How can I open the window to removed the locking handle?