Rocker Panel Clips
Laysons lists the "plugs" that hold the clips on. Part # GM-1510. Don't know what to tell you about the clips. I have several new ones I bought from my Mopar dealer about 30 years ago, but not even enough for my car. If anybody finds repops I'd be interested too.
baucco, you posted while I was looking for my Layson's catalog. I'm interested in more info on the spring clips too.