sash guide ?

Hello, thank you for posting,

We can assist with a replacement, but to further review, we will need to see the inside of the metal channel where we can view the connection point between the spring and pulley system. From there we can narrow down the correct series for your window. Thank you! 

Thank you for the additional pictures, 

It appears you have either the Series 351, with a 15-002 bottom attachment, or Series 390, with a 15-001 bottom attachment. Take a look at the image below to determine which balance you'll need.

The length of the metal channel excluding the nylon attachments should measure 28 inches long and you will need a 2730 stamp option. Please review and let me know if you have any additional questions! 

Comparison of the S351 and S390 balance shoes.