Window Tab - Replacement Part

Hello! I recently purchased our current house built in 1996 with CertainTeed windows. One of the tabs that holds the storm window in its track when open or closed is missing. (Pictures attached of where missing part goes and example of the part on other side of window). How could I go about replacing this part?

Thanks in advance!
Dan

Just ordered it - looks like a perfect fit.

This is an awesome part finding service by the way... thank you!

-Dan