Windshield would be my vote if the doors are too small.
Be careful, most use a gasket. You don't need a glass shop, you can reinstall it with two people and a few you tube video's.
The newer the bus, the less I can tell you. But, newer buses use more curve and less cheap to replace flat glass.
"Don't argue with stupid people. They will just drag you down to their level, and beat you up with experience."
Patently waiting for the apocalypses to level the playing field in this physiological game of life commonly known as Civilization