Have you tried these guys:
Antique Gas Stoves - Antique Vintage Stoves
Most likely O'Keefe and Merritt would probably have used the same door hinge on both their gas and electric stoves. I know this company sells the door hinge springs, but you'd have to find out if they sell the hinges. Maybe they know of a local fabricator that can repair the hinges.
Their phone number is 909-484-2222 and you can e-mail them at:
cookin@AntiqueGasStoves.com