GbL member JDubz says: "HARDWARE - BASS STRING RETAINER - RECTANGULAR (in G&L's On-Line Store)
Is a direct fit to my 84 Skyhawk."
Here are some photos of his '84 Skyhawk showing the replacement string retainer:
Here is the link:
HARDWARE - BASS STRING RETAINER - RECTANGULAR.
Special thanks to JDubz for sharing this information and his photos.