Help identifying fender nut/clip
 

In the process of doing some extensive rust repair on my first benz, a '78 300CD. Each fender has two mounting points on the rocker panel where metal spring clips engage the screw. I cannot for the life of me find it on any parts diagram or anywhere on google. I'm sure there is a terminology I'm not searching correctly for, but "nut", "clip", "retainer" are coming up empty.

Attached is a picture showing the location and (damaged) clip.

Thanks in advance.

Another hour of searching, and I think I found it.

0019940845 "Lock" - Front fender to side member.

MB fastener referencece guide: Life-size (1:1 scale) physical photos with MB part numbers for future searchers.:)

A0019940845 (PRESTOLE CAGE NUT) is image 220 in the link.