An odd piece that is also very early-on in the history of Canadian Porcelain products. This heavy, chunky crown is characteristic of the first generations of CP-marked multiparts. It is flat-topped with slanted edges and has very narrow wire grooves cut into it. This style probably dates to the mid 1910s - possibly as late as 1920 or so. The pinhole is 1 3/8" wide and is unglazed (unglazed pinholes are typical of early CP products).
Two other styles are found with a similar crown shape. One is the [id=473783837;M-2508], and the other is [id=475103539;yet to have an M-# assigned]. I will post a photo of this last one in due time.
Glaze colours found in this style are just as in this example: characteristic mottled red-orange-brown early CP glazes.