Caldwell Balancer - 26 4 GQ CALDWELL

Hello,

I need a pair of balances for one Milgard window, please.
The window is date/stamped ?AUG 22 1997? which I believe is the date of manufacturing.

Pictures of balancer attached.
It is stamped:
"26 4 GQ CALDWELL"

I believe it is a 15P142 top, winged.

Bottom is winged, as well.
But the measurement is right between 1-1/8? and 1-1/16? front to back.
So I?m not sure if bottom is 15P170 or 15P102..

Any thoughts on which bottom it is?
Thanks!