The window pivot shoe broke
Thanks for these photos, these are a huge help. Does your balance have a simple hook at the end of the cord, that then connects to the shoe? If so, my recommendation to replace that shoe is our 15-208. Look this over and see what you think, or let me know if you had any questions!
Are you referring to the height or the width? Height isn't a big deal, but width is pretty important.
I would make sure to remove yours from the window before you measure just to be 100% sure as to its size. 1-1/2" for width is very odd. 1-1/4" is pretty much the widest you can expect to see of pivot shoes except in the most unique of cases, and I don't think you have one of those cases.