There is an aluminum trim piece that is just behind the glass panels. I believe it runs the full width, behind both glass panels.
It looks as if a previous owner was not careful when installing the glass and hit that trim causing a wrinkle and slight tear. It seems to be fairly thin gage material.
Are there any sources for replacement parts?
While the clip is being replaced it seems like the perfect time to replace it if possible.
Is it riveted to the black plastic trim piece? That's probably the "p" seal. It normally has a bead of plastic next to the top edge, and a felt covering. Hence the name... The cross section is shaped like the letter P. I don't think there are any more around, but the ones for the late 80s Mustang T-tops are fairly easily adapted.