Call it deja vu.
The simplest, cheapest, and best solution for a coolant pump dying is to shut down the still. The only reason you'd want a redundant pump is if there is no one around to notice the pump died.
There are hundreds of things that could possibly go wrong, a pump dying is just one of them. Maybe a hose burst, maybe water main pressure failed, etc...
I do have two pumps, but not for redundancy. One runs during spirit runs, the other during stripping runs. If both fail I could run off of city water. But again, that's not for redundancy, it is for efficiency.
BTW, a spare pump is a perfectly good idea.