Well the basic story is the NZ Longbranch and Savage rifles were supplied in or around 1946/7, out of commonwealth stocks stored in Italy. They were part of the post was division of surplus military material, in lieu of actually payment of specie. The quantity supplied was in the 45~48,000 range. They became the post war issue rifle of NZ, and remained so until the replacement by Lithgow
made L1A1 rifles circa 1962.
The disposition was as follows:
1) Quantities sold to Century arms circa 1965/66, which is where the ones in the US of A come from, though these are always Longbranch made rifles, at the time Savages were not allowed for import due to a 1959 act.
2) Sold to NZ citizens for marksmanship use and other purposes (hunting) up to around 1978.
In NZ Full bore competition the No4 was the rifle from around 1948 (once good target sights became available in quantity) to 1968/69, when the 7.62 NATO round took over. NZ made some of the most accurate non-corrosive MK VII ammunition in the 1958/59 time period and it sort of set a standard for competition in the 1965 to 1969 time period, at least in Commonwealth matches shot in NZ. Indeed the visiting UKteam in 1968 bought quite a quantity to take back home.
I am sure I have a lot more in notes, but that is what I recall off the top of my head.