Hey there, thanks for reaching out! The double support appears to be our 15-181 double support detent clip. This is typically used along with the 15-180 coil balance shoe. Look over the dimensions for the shoe below and compare them to an existing, undamaged shoe. See if these are the right fit for your window.
These pieces of hardware are compatible with 15-182 coil bushing and the Series 190 Coil balance spring. To confirm the right replacement springs for your window, you'll need to look for any stamps/markings on the metal coil.
If there are none, you'll need to obtain the exact window weight and divide it by the total number of coils. Then on the list of balances the first number after the 190 will be the weight you'd need to select.
(For example, if your window ends up weighing 24lbs, you'd need (4) 6lb coils. So you would need the S190-640.)