Aliside Ultramaxx window - broken shoe/balance

Thanks for reaching out to us! This indeed looks like the 15-177. If the specifications match up then you're good to go! For a 14-pound window sash, I recommend using one S152-7 7-pound spring on each side of the window. Take a look and let me know if you have any questions. 

The coil springs are sold separately from the pivot shoe. The spring is then attached to the side of the 15-177 using a screw like the 33-072.