A question for Australian and New Zealand members from North America:

[Capt.Mainwaring]

The rifles were possibly intended for the Canadian Army in Hong Kong, which fell on Christmas Day 1941.

No.4's were also used by the Volunteer Defence Corps. From the AWM collection #063000:
"YUNGABURRA, QLD. 1944-01-16. LANCE CORPORAL J. S. RUSSELL OF NO. 10 PLATOON, 17TH BATTALION, VOLUNTEER DEFENCE CORPS GETTING THE FEEL OF HIS NEW RIFLE AND BAYONET"

#063700
MOSSMAN, QLD. 1944-01-24. THE SECOND IN CHARGE OF E COMPANY, 17TH BATTALION VOLUNTEER DEFENCE CORPS INSPECTING TORRES STRAIT ISLANDER MEMBERS OF THE UNIT. LEFT TO RIGHT: Q219685 LIEUTENANT A. J. MORGAN; Q219728 PRIVATE D. PITT; Q219716 PRIVATE P. JOSE; Q219698 PRIVATE W. AH WONG.