Jamming around 80 and felt something hit my left foot...pulled off and noticed a crucial bolt was missing. Started looking for a replacement from somewhere else on the bike and came up empty handed.
Ended up using a couple bent-up keychain rings to get some semblance of shift-ability which, would last about 4 shifts before coming apart. Thankfully, it was enough to get me down the road and to a auto parts store to get a bolt and lock-nut.
Special thanks to Pickett and Frank for stopping, providing a crescent wrench and staying until I was back on the road.