[paw broon]

The date isn't estimated, it's slightly wrong. Actually 1949, from a book titled "The Early Australian Comics" unfortunately I don't know the author. As to the art, the first 19 issues were drawn by Jeff Wilkinson with Peter Chapman taking over from #20. Big difference in style and quality.
The format also helps date the book. This really odd format of upright cover but landscape interiors was only used early on and for a short while in Australia. Aus. publishers also used landscape format, covers and interiors, in the same way as in Spain, Italy, France and Netherlands, where it was used for hundreds of titles for a much longer time. Format Italien is a term widely used.

Link to the book: The Phantom Ranger 002