need source for trim clips '63 Dart GT

No luck so far on locating a source to replace the 10 plastic push-in trim clips for the roof/quarter panel trim on my'63 Dart GT. Haven't pulled the side moldings off yet, but I suspect there will many more underneath.

I was able to remove the clips by drilling a hole in the center push-in post and threading a sheet metal screw in to extract it...remainder of the clips are not in the best of shape after a half-century of use (nor am I!)

Any leads appreciated!