Another option for a chain whip is either a piece of nylon rope or 1" web strapping. Both very lightweight, can serve other purposes and work quite well. Just loop around the cassette and your foot and it's done.

Though I generally carry extra spokes, the nice thing about the universal Fiberfix kevlar spoke is that someone else in your party will appreciate it if they came less prepared. Travelling in less populated areas as I do much of the time demands that I can't rely on a bike shop within a day's ride.