You can buy an adapter on Amazon to connect the old style plumbing to modern hoses, if they're the same in NZ as in North America,
With a trailer that age the plumbing is probably iffy at best, I ended up replacing all of the plumbing on my trailer.
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1977 Safari Land Yacht
2005 Toyota Tundra SR5
2022 Toyota 4Runner SR5
That is a Thetford connector. They are still available, and as AldeanFan mentioned, an adapter is also available to connect a Valterra connector/hose to the Thetford pipe on the trailer.
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John
WBCCI #268 Palmetto State Airstream Club 22
Region 3 Past President....come with us, you will like it.
Go often to the house of a friend, for weeds choke the unused path........Emerson
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