The short version
14 companies supply this market — deep enough that no single failure threatens the supply. The generic price has fallen 33% in a year, to $8.87 per mL — and generics that get this cheap tend to get abandoned rather than defended. The brand (Latisse) runs $103.01 per mL — 12× more. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
The numbers behind every sentence are on this page below — and the Watch button emails you when any of them move.