I've looked and can't find any reference to plates like that. Must be extraordinarily rare. You may have an extremely valuable license plate there cryptic. Don't sell it until you learn more about it. It could easily be worth over 300, maybe even a lot more than that.
That may be the best thing you'll manage to pull out of that entire dump!
I found a couple others, none quite as early as yours:
"DRAY
There are three dated varieties of Dray plates known - one from 1911, two
examples from 1915 and one from 1929. These are nearly identical in layout and
appearance, and very likely were issued from the same jurisdiction. These plates
could have adorned either horse-drawn carts or motorized trucks" From this Porcelain Plate Forum. You might wanna give their site a visit.
"The plate shown at left would have been issued to operators of drays or express wagons within the City of Vancouver. The date at right make the year of issue easy to determine. For those unfamiliar with what might constitute a "dray", it would have been a low heavy horse cart without sides that was used for haulage. It is assumed that a different classification of license would have possibly applied to motor vehicles." From.
"A 1915 Edmonton Alberta dray license. These were issued to horse drawn commercial vehicles in Edmonton at that time. When I obtained this plate it came with the original mounting strap which was attached somewhere on the horse, which I believe was above the eye. Brass plate with debossed numbers filled in with black paint." From.
A double dray license plate from Portage La Prarie, Manitoba 1912 #13. A double dray is a two horse team licensed for hauling a commercial load for business. This is an equestrian version of what would be a commercial license plate on motorized vehicles." Same guy.
UNDERSTAND THIS TOWN WAS REAL SMALL IN 1922 AND NOT ALOT OF CARS HERE THEN...THEN TOO ...THAT A PERSON GAVE $2000 FOR IT MAY JUST MEAN THEY HAVE TOO DAMN MUCH MONEY! JAMIE
Thank you for the contributed information everyone. I'm not sure what I will be doing with this plate right now. I don't really have a place to display it but I will hang onto it and eventually display it with great pride. It's a piece of history!
I received an email from someone that is very knowledgeable about license plates in my area.
"Thanks for the link to that most unusual plate. If it is indeed Ontario, it is nothing like anything else the province has issued. I am not aware of any places having Dray plates from that long ago. Even Toronto isn't known to have had them that far back, and if they were issued, it's likely a few would have turned up by now. I find it possible, though unlikely, this is an Ontario plate, especially for a smaller town like Cobalt. Finally the dies on this plate do not suggest any kind of manufacture in Ontario. To me, this looks more likely to be something from Minnesota, Michigan or NY. A bordering state would be plausible - someone moving to Ontario, no longer needing the plate and turfing it away. Also consider that any cross-border cartage company would have required a license for the US side of the business, if one was mandated. Unfortunately this plate could remain a mystery for a very long time - without any photos or documentation it may never be resolved as there's nothing on the plate to suggest where it is from. Sorry that I could not be of any real help in this situation. - Joe Sallmen(Author of 'Ontario License Plates - A Century of History' published in 2003/04)."