I need help finding a set of balancers

Hi there! 

Our S770-28 looks like it'd be a good match. The stamp doesn't match any of our options though. That means you'll have to weigh the window sash on a scale to determine the proper option. There's a chart under the product description on the S770-28 store page that you can refer to which will tell you what strength option is best based on the sash weight. 

The pivot shoe might be the 15-129 but we recommend you compare the dimensions and style with yours to confirm.

Detail of 15-129