This bottle was found in Western Canada. Anyone ever seen one before? It was made by Dominion in Hamilton, Ontario. Possibly 1942. Anyone seen the "it" before?
I haven't thoroughly read all of the comments. But a similar mould with different base is not uncommon. Also, there were moulds that could have a removable metal piece that would change a number, name, or whatever. So if it was the same mould, not all that unique, but I suspect it was just a...
Pharmaceutical bottle, I would think. Something like Castor Oil or such. The date is post 1904 and, yes, likely before WWI ended. I have a bottle with a similar mark on the base with the "S" being reversed, but I doubt they are the same company as mine is a beer bottle and was mould blown.
It's pretty common - I suspect it comes from the glass and the mould being different temperatures. Some moulds also had a paste put in them and that might have affected the glass. I hope you know that "metal" means molten glass in this situation.
At least you knew it COULD be a glaring repro and knew to ask. I'm sure someone might have quit the job and walked to the nearest pawn shop to make their millions LOL.