The bottom of the window balance (spring) was broken.

Hello, thank you for posting,

Your channel balance resembles the Series 795 style balance with the 15-198 hook at the top for installation. This configuration will require a custom order to assemble for you.

To further review, do you have an identical balance where the T-lock shoe at the bottom is undamaged? We need to see the style to confirm the size and if it has a closed or open(see through) metal cam that accepts the pivot bar on the sash. 

Please also confirm how many you need. For custom orders there is a minimum of (2) balances required. Thank you!