Balancers for Andersen double hung window

It's hard to identify a balance based on just the glass size. If this is a Narrowline Andersen window, then I recommend our 24-1133. However, you may want to remove the balance from the window and tell us what numbers are printed on it. That would give us a better idea of what you have and what can work as a replacement. In fact, it would be even best if you were to take a few pictures of the stamps in question. Sometimes seeing how the numbers are printed is just as important as the numbers themselves.