Vox in Australia
It is probably worth saying as preliminary that Jennings - "Jennings Musical Instruments Limited" as it was at the time - had certainly begun exporting equipment to Commonwealth countries in the Southern Hemisphere by the mid 1950s. Below, an advert in a New Zealand paper from February 1956:
The "Upper Hutt Leader", 23rd February, 1956.
New Zealand papers also carried news of the annual "British Instrument Fairs" held at various venues in London in the 1950s. Home from home.
Although no similarly early advert from Australia has come to light so far, it is clear from the small ads in the "Sydney Morning Herald", that the Univox keyboard was present and available from at least 1954. The earliest illustrated ad., certainly where the Herald is concerned, seems to be the one below, from September 1958:
The "Sydney Morning Herald", 9th September, 1958.
Note that the Univox is simply the Univox, not the Jennings Univox. Mention of Jennings / Vox amplifiers does not come until later, however.
This at present is the bare bones. A particularly valuable source is hard to come by - "Music Maker" magazine, a popular Australian musical periodical that had its beginning in the jazz world of the 1940s. It is not to be confused with the English magazine of the same name which ran for around 18 months from late 1966. Info from Music Maker (Asutralia) will be posted as it comes to hand.
The magazine has, for instance, this great advert for Vox featuring "The Atlantics" - picture from this page.
"Music Maker" magazine, late 1964. Note the mention of Nicholson's of Sydney, Sykes in Melbourne, and Grice-Nicholson's in Brisbane.
So far as Sydney is concerned, the first shop to mention the arrival of Vox equipment was "Guitar City" in the "Sydney Morning Herald", 15th March, 1963. Note the presence of "soon":
The entry above is from the "Sydney Morning Herald", 23rd March, 1963, simply for the sake of clarity. The entry is exactly the same as the one placed a week earlier.
But the first indication that Vox equipment was actually available at "Guitar City" came on the 11th May 1964:
"Sydney Morning Herald", 11th May, 1964.
Nicholson's followed suit a few days later, having mentioned very little relating to Vox in its adverts up to this point ("new Vox guitars" on 15th December, 1963, but nothing else):
"Sydney Morning Herald", 16th May, 1964.
By June 1964, Nicholson's had become the sole Australian distributor, placing a handsome ad in the Beatles' Australian Tour programme, and larger illustrated ads in the "Sydney Morning Herald".
Nicholson's advert in The Beatles' Australian Tour programme. The Tour ran from 12th-30th June, 1964
"Sydney Morning Herald", 17th June, 1964.
Below, an advert placed in the "Canberra Times", 29th June, 1964, by Donoghoe's Music Centre, Queanbeyan (nr Canberra). Donoghoe's had signalled the availability of Vox amplifiers on 15th June, but only as part of a general indication of what was in stock.
"Canberra Times", 29th June, 1964. The ad is a version of the one placed by Nicholson's earlier in the month in the "Sydney Morning Herald".
Various pricelists and catalogues were printed by JMI for Nicholson's (and Sykes in Melbourne):
1966 prices. Picture from Jim Elyea's book, collection: Martin Kelly. Note that the "AC30 Expanded Frequency Twin Fifteen" is still available.
Late 1966 - promotional brochure for the solid state range, available in full here.