Those bayonets SHOULD be "close".
They were made using copies of the original Lithgow drawings, for both the bayonet components and the gauge for the final form of the blade.
The bit of history missed by a lot of "enthusiasts" was that these bayonets were devised for Australia's rapidly developing Airborne troops in WW2. Airborne troops? They took part in some f the more "interesting" back-water campaigns in the SW Pacific. Australia also fielded Ski Troops in the mountains of Syria and Lebanon, just because they could.
Anyway, officially, and on the drawings, the bayonet in question is referred to as; "Bayonet, Parachutist".
It plugs straight onto a No1 Rifle nose-cap. Ditto the nose caps on the trials "shortened and lightened" carbines trialed around the same time. The correct name for these carbines is: Rifle.303", Intermediate, of which there were a couple of variations. These lead to the Rifle, No1 MkIII*, Lightened Patt. (Aust). often "short-handed" as the "No.6" series.