Trim Clips 70 GTX

Hi. I am looking for trim clips for the rear quarter caps trim on a 1970 Plymouth GTX. They have like little rubberized pieces on them so no water gets in. I called RT specialties, and I tried Megaparts with no luck. Does anyone have measurements? I saw clips on eBay but I am not sure if they are the right ones. Thanks.

I believe the little rubberized pieces are just body sealer....not sure about the clips. Are they small "speed nuts" by any chance? A picture might help if you have one.