Find a suitable window pivot bar

Hello,
I am trying to find a replacement window pivot bar that would closely resemble the original. I can't locate a window brand and have tried a few pivot bar such as the metal U-shape pivot bar but it does not have sufficient backing/housing to prevent it from moving around.

Is there anything that would resemble the original window pivot bar like the one attach? Please advise. Many thanks

I can't figure out how to remove the working windows. They don't easily retract away from the shoes.