Andersen sash balance D94 7#27 9 79 replacement needed

Hi,

I'm trying to find the correct sash balance for my 1979 Andersen windows. I have the old balance out, but I'm having a hard time identifying the correct replacement I'd need from your site. Below are the numbers I have stamped on the balance...can you help me find the right product?

D94 7#27 9 79

11600-2
11600-3 (I'm guessing these are the case component numbers)