FS Squarish British gas can

[Ron Pier]

Those pictures are of the fairly common 2 gall petrol/oil/water can. The Canadian version would also have the maple leaf with a C round it embosed on the bottom.
The 4 gallon Flimsey is as stated and a very rare item. A poor quality, more or less throw away can, which was replaced from about 1942 with the captured Jerry Can design. Ron