69 Barracuda Rocker Molding Clips

I don't know the size of the pastic piece you are showing, but these work on the belt molding on my '64 Valiant. There are measurements in the ebay listing.
https://www.ebay.com/itm/25-pcs-NOR...hDarwoV3BBEV2b&_trksid=p2047675.c100005.m1851