New 914 flappers are NLA. Replacements are actually bus units with a small but meaningful difference, and they aren't cheap either. I sell them for $110.

If the housing is ok and the hinge mechanism is still intact but the springs which hold the discs apart inside are broken, the flapper can be repaired easily. In fact, the hardest part is removing the rivet that holds the assembly together.

This pic shows the two springs that were inside a flapper box I repaired this morning.
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This conical spring is significantly smaller in diameter than the original but it's the biggest I could find.
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This is where the spring goes. The cone is reversed from the original orientation but this benefits the assembly in a way that makes the other spring unnecessary.
After bolting it together it works perfectly again!
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I can sell one spring and bolt/nylock as a repair kit for $12 plus delivery.
I can repair two flappers for a price of $60 + return shipping.
Depending on demand I might be able to establish a lower price but I would have to buy 100 springs at a time.