Channel balance
Your coil shoe reminds me of the 15-199 Pivot Shoe. While I am confident this is the correct replacement, be sure to look over the dimensions and compare them.
The compatible coil springs are the 1/2" Series 160 Coil Balance and the 3/8" Thick Series 165 Coil Balance. You'll need to confirm the thickness of your springs to determine which of these is the correct series.
Once you've confirmed the series, you'll need to look for stamps/markings on the coils to determine the spring strength needed for the assemblies. If yours do not have them, please take a look at the video tutorial below for detailed instructions on how to select the correct springs.
You'll find the compatible balance spring covers in the related items of the appropriate coil.