Where to find a Fisher and Paykel Smart Drive
EasiestThe easiest is ebay, you can pick them on the Australian/NZ ebay site for around $AUD50.
CheapestIf you are lucky enough to live in a country which stocks Fisher and Paykel washing machines then people throw them out. At least once a year you will see one on the side of the road (I've picked up all mine that way here in Sydney). If not the tips have lots of them (if you can convince them to let you take one out of the tip these days).
GuaranteedIf they don't have any the next best place is Eco Innovation but they are a bit pricey.