I have used both my local glass companies by making a cardboard pattern and bringing it to them, well-labeled.
They buy large sheets of 1/4 inch laminated glass (2 thin sheets bonded with a plastic layer in between that measures 1/4 inch total thickness) and cut it/sand it to fit my patterns. If the glass breaks, the glass stays attached to the plastic, making it safe. It's what modern windshield are made of. You don't want tempered glass as if it shatters while you are driving, you have a million little sharp pieces flying at you.
They have it available have it either clear or tinted(green or grey).
It cost about $75 for each side glass and $100 for a windshield and $50 for the rear glass of a 1932 Sedan.