Looking for the right part(s)

Hi there, I was hoping someone could review the following and let me know which part would be appropriate for replacement. I broke the "spline" I think it's called on it when I over-cranked it to close the other night, so now it will open but it spins out of the casement when I try to close the window and it won't close. So not sure I can just replace the "spline" or what is all needed? It's for a tilt window that opens out and when you crank the lever, which as you can see, is in the middle of the casement it spreads with two arms and opens the window from both sides, running along a track on the bottom of the window, making it open evenly at maybe a 30-45 degree tilt. It's for a basement window. At any rate, I have added some photos and if there's something I need to measure first before ordering, please let me know. Your help will be greatly appreciated. Thank you!

Dave

Fantastic, thank you so much. I swear I looked through everything and never saw this, but without your help, I probably would have ended up getting the wrong thing, so again thank you so much.

I definitely won't, as I bought a house with all crank windows, so there are many different types that will break at one point. Thank you again!