Gill et al - You are correct. The rifles were supplied to England under Lend-Lease and “related programs” (according to Canfield - perhaps there were some actual purchases as well) in late 1941 and 1942, The deliveries were kept secret for the most part, as the U.S. military at that time was short of small arms and the American Public, especially before Pearl Harbor, probably would not have been too happy, as Canfield points out, to hear that the brand new U.S. Service Rifle, in very short supply to U.S. Forces, were being shipped overseas.
As Gill pointed out, they were marked in England with a red band painted around the front handguard to signify that they were a different caliber than the standard .303" cartridge, and evidently the number “.30” was painted on many as well. Most of these Lend-Lease weapons were issued to the home guard and few, if any, saw service with British troops abroad. They bear British proof marks, but these were not applied at the time of delivery from the U.S., but rather pursuant to British law, the guns were proofed before being exported back to the United States, with the marks applied at that time.
I could find nothing about the Canadian rifles, but my impression was that most showed rebuilding - parts of post-WWII design, and they may have been sent for use by the Canadian contingent of the UN Forces in Korea. I don’t know how many troops went from Canada, or what weapons they used, in Korea. I know that the Brits used their own Rifles Number 4, as well as the usual assortment of Stens, Brens, etc.
The only Canadian use of the Garand of which I am aware was with the joint US/Canada Mountain Brigade, the name of which escapes me right now, that
was formed during WWII. The Canadians trained with the US, wore the same battle dress as the US troops, and used US weapons. I don’t know if they took the rifles back to Canada when the unit was disbanded or not, but I tend to doubt it.
Regarding the shipment of U.S. Arms to allies at the time the US was short, I have a Remington Model 1903 “Springfield” rifle of the earliest configuration, barrel-date 11-41 and serial number in the high 7000 series of Remington’s numbers (30078XX) that was sent to New Zealand, probably soon after or just before Pearl Harbor, and remained there. Its 95% condition and total lack of any alterations or refinishing, other than “NZ^D” and a number stamped in the left side of the butt stock, indicate it probably was never used or even issued.
Reference: “Bruce N. Canfield’s Complete Guide to the M21 Garand and M1 Carbine,” page 73.