I was flicking through a Whites Air Guide from January 1964... thought some of the bits and pieces might be of interest!
At that time, New Zealand was thoroughly behind the times in international aviation. Most of the regional airports were still grass strips, although that was changing (the current Hawkes Bay Airport, with a tarmac runway opened unofficially in December 1963, and officially in February 1964). Several other regional areas recieved tarmac runways or entire new airports throughout the 1960s. And although Christchurch was (believe it or not) a first class airport even then; and DC-8 and 707 capable, neither jet serviced the country commercially as Auckland-Mangere was still under construction, and the runways at Whenuapai were not long enough, and the government wanted to save the fanfare for late 1965 when Mangere opened.
Meanwhile large jets continued to serve Christchurch for the Antarctic operations directly from Pago Pago and Honolulu.
Both Wellington and Whenuapai had a lot of RNZAF or chartered civil flights bringing in immigrants; mainly from the UK but also elsewhere.
So the only commercial jet service was twice weekly (Tuesdays and Sundays) from Whenuapai to London Heathrow with BOAC on the Comet 4; via Sydney, Darwin, Singapore, Rangoon, Calcutta, Karachi, Damascus, and Rome. It sounds very exotic, probably was, and cost the princely sum of NZ£253 one way economy class.
Other options: fly on a DC-4 to Noumea (once weekly, Fridays) and connect there with Transports Aeriens Continentaux to Paris by DC-8 or to Tahiti and Los Angeles with UTA/Air France on a DC-8; a DC-4 also serviced Norfolk Island weekly (Sat, sometimes Sun as well).
Pan American flew a DC-7C to Nadi and then a DC-8 from there to Honolulu.
Canadian Pacific flew from Whenuapai to Honolulu with a Bristol Britannia on Saturday, then DC-8s from there to Vancouver and Amsterdam.
It seems strange to think that Nadi, Noumea, Pape'ete, and Pago Pago were DC-8 capable when Auckland wasn't!!!
Trans-Tasman service was by L188 Electra with both Tasman Empire Airways Ltd and Qantas. They had a combined schedule so I cannot tell you who did what, but even back then, there were flights at least once daily from Whenuapai to Sydney, sometimes three times a day. But Brisbane had only two international flights a week!!! (One to Wellington on Saturday and one to Auckland on Sunday).
KLM flew from Sydney to Amsterdam, Air India from Sydney to New York via Bombay and London, Alitalia from Sydney to Rome, and Qantas from Sydney to London via all sorts of exotic ports, and probably all over the Far East as well, although that isn't detailed on this guide.
Whenuapai to Sydney return cost NZ£65/6 economy, and NZ£84/15 first class.
There was a rumour of turning Paraparaumu into an airfield capable of handling DC-8s, but sadly, that never happened, and Wellington is STILL stuck with Rongotai!!! (Rongotai was however made DC-8 capable - just - later in the decade).
And a round world fare cost NZ£480/14 economy, and NZ£750/10 first class.
I am lousy at trying to really estimate how much that would be in todays dollars (I wish I could!), but I CAN say that in 1964, NZ£750/10 would buy you a small house, or at least a flat!!! I have a suspicion that it cost around NZ$5000 in today's money to fly Auckland-Sydney return.