Coil balances
Thanks for posting! The part you have pictured here is referred to as the double support detent clip, part 15-181. This is typically compatible with the 15-180 pivot shoe and the Series 190 coil springs and the 15-182 coil bushing. To confirm that these are the exact replacements you'll need, you'll have to remove the coil balance assembly from the window and compare the dimensions of the shoe.
To determine the coils springs needed for your new assembly, you'll need to look at the metal coils for to confirm that the spring strength, then select it from the list of Series 190 coils. The first number is the spring strength (i.e. S190-740 would be a 7lb coil).
If there are no stamps/markings on the coil, you'll need to take the exact sash weight and divide it by the total number of coils in the window.
Take a look at the video below for instructions on how to remove these from the window.