Window balance parts
Hello,
Your coil balance pivot shoe looks like it could be the 15-228 Pivot Shoe. Although, it is a bit difficult to tell from the photos of the assembly because it is obstructed by the frame. Once you are able to remove the shoe from the window, you'll need to carefully compare the dimensions below to determine if this is the right replacement.
This shoe is compatible with either the 1/2" wide Series 160 or the 3/8" wide Series 165 Coil Balance springs. To determine which of these series you have, you'll need to confirm the measurement the width of your coil spring. You'll either need the S160-7 or the S165-7.
The compatible cover will depend on the exact coil spring needed for your repairs.
Take at the videos I've linked to this post for an idea on how to use either the jamb spreader method or the cutout method to remove the shoe.