Looking for help

Thanks for writing in! Given the confirmed dimensions, you'll need the S900-29 Spiral Balance. Since the sash weighs 17.2lbs, I suggest using the red tip option.

Your pivot shoe appears to be the 15-045 3/8" Thick Pivot Shoe. I am confident this is the replacement shoe you need but be sure to confirm the dimensions below.

Dimensions for 15-045

The two pivot bars most commonly used with this shoe are the 26-041 2" Keller Pivot Bar and the 26-297 2-1/4" Pivot Bar. Take a look over the dimensions and design of each of them. If neither of them are a match, I'll need to see a photo of your existing pivot bar removed from the bottom of the sash.

Alternate image for 26-041

Alternate image for 26-297