Messed up door lock

My driver's door lock looks like someone tried to jimmy it with a screwdriver at some point (it's been like this since I bought the car, btw). Well, because that flap is missing, the lock gets crudded up and stiff sometimes. Is there a way to fix this without getting a whole new lock? If not, is there a way to get one new lock and have it keyed to match the rest?

Pix below, with the good lock for reference.

You could try disassembling the lock cylinder. IIRC the trunk also has this flapper and it was removable.

Rick, a good lock can be re-keyed at a locksmith.

Many drivers side locks have the same problem.

Your key code is on the passenger door lock mech.

Thanks for the info guys... I'll dig around in there this weekend, hopefully.