Ok, I double checked my extra convertible trim & you have the correct clips. What holds those onto the car is simply "machine screws" that you can buy at a hardware store.

The factory ones are slightly beveled at the tip to make them easier to install, but nobody will ever see the screws, so hardware store is fine in my opinion. Just be SURE the screws you get aren't too long or you will dent the trim tightening them down. The screws come up from under the pinchweld lip, through those holes, into the holes in your trim clips.

You might need to custom-cut some hardware store screws. If so, then maybe run a die up on the screw, cut them in a convenient way, maybe even bevel them slightly, and back the die off the screw to clean up the threads you just cut.