Yep, NZ is lucky in one respect as to getting a good range of cars but boy we were stung with some piles of shit. I was reading recently that Auckland (our largest city) is second only to Los Angeles for cars per head of population which proves we are all petrolheads. The figures are the same for Ferraris and HSV Commodores.... but we also get Skodas, Ladas and Yugos.????
As to the Viva connection I'm not sure but all cars of the era seemed to have springs of the same dimensions. I've got springs from an MG Midget in the front of my coupe , they are as hard as hell and dropped the front 3 inches (75mm for you youngsters) but are more suited to track work than street...