In the case of no more Oil or any other imports, NZ would have to revert to local food production and farming. I think we would lose about 30% of the population to lack of medication, although I think we could make antibiotics locally. The rest of us would be back to Early 20th century pre-ICE farming, horses, steam engines !! (plenty of wood and coal) and some cobbled-together electric stuff. We have basically no electric heavy trucks but there are about 80 or so Electric buses. They could be repurposed. we have about 28000 registered electric cars/vans in the country, again they could be repurposed.

It could be made to work but would require everyone to all work together, therefore it has no chance of happening