The '76 I am working on does not even have this window. Could you not fet a local glass shop that does screens to build one? Maybe take in one from another window as a model, and tell them what measurements you are looking for.
2017 Escape 5.0 TA
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
“Most folks are about as happy as they make up their minds to be.” — Abraham Lincoln