Replacement Window Balance Part Identification

Hello, I'm looking to replace a pair of window balances with the details below.

27-4 marked, 28" measured metal length for the channel.
Plastic bottom is approximately 1" tall and 1 1/16 or 1 1/8" deep
Metal hook is 1/4 - 5/16" wide
Plastic top is about 1 1/4" tall and approximately 1" wide

Please let me know if you need any additional photos or details.

Thanks, I'll give those a shot.