Vinyl top trim fasteners - looking for source

I ended up using the same clips that are used on the rest of the vinyl top trim. They work fine but are a pain to install (getting the nut on the back). I think Chrysler used those odd screws because it would be too expensive to have a factory line worker crawl into the trunk and snake their arm up above the wheel well to do this, but for us it's all in a day's work!