When it comes to helmets on Canadian heads you have to refer to Roger Lucy's authoritative book "Tin Lids - Canadian Combat Helmets" published by Service Publications.
In mid-December 1942 Canada contracted for 250,000 US M-1 helmets. This was on the false belief that the UK was going to adopt these. By the time Canada realised its error, a large quantity had already been delivered and, in 1st Canadian Army, the PR announcement had already been made. (See photo)
Canada handed some over to US Army in NWE but kept most for use by Pacific Command and 6th Cdn Inf Div, later the Cdn Army Pacific Force. These helmets remianed in Canadian stock until replaced by the PASGT helmet.