Mullion tension clip

Hello;
I am looking to replace damaged or lost aluminum (I think) clips on the mullions (perhaps it's called a "door grill"?) on my sliding porch doors.
Can you help me?

Hi again, Swisco: in response to "support" of a few minutes ago, here is a closeup photo of the fastener I'm currently using. Do you stock these? Do they come in different sizes? Is there an alternative that would do a better job?