[MBAtarga]

I've been "stranded" three times with my SC in 19 years of ownership.
Clutch cable broke within first year of ownership. Had an acquaintance that lived nearby and he was able to tow me using his pickup truck about 2 miles to my MIL's house. I was able to source the replacement cable in a few days and installed it myself at her house.
Second time was a dead batter - could have happened with any vehicle.
Third time was the CDI unit gave out while running an errand. I wasn't able to diagnose it myself and had the car towed the 2 or 3 miles to a local mechanic.

So - I'd say clutch cable spare - or replace it as PM if you don't know the age. CDI spare as well. I also carry both red and black spare fuses.