... well, perhaps. But, perhaps more possible than you think. We DO like to think that the things we find are unique. Yet, look around YOUR house at the odd things you have. Anyone of which can be lost for the next detectorist.
Florida has been a popular destination about as long as the populace has been able to get around easily. Too, Canadians and Americans have enjoyed a long history of commerce and intercourse for as long as, well, as long as there has been a Canada and America. It's not such a stretch, really. Now a 1945 Finnish coin - that might be an oddity.
We tend to like foreign coins, as they are "neat" to us. Many carry them around for that reason and some even consider them good luck. I have a 1932 Wheatie I got in pocket change recently, that I hung on my bulletin board. Thats how neat-o I considered it!
Also have you heard about the "Eight-Ten Rule?" Most coins in your pocket are, on average, eight to ten years old. Try it. Pull out all the change in your pockets and that of your family members and add up the dates, then divide by the total of coins for the average. How close to 8-10 years old are they, on average? Pretty close, I'm willing to bet.
In the old days when people were more tight fisted with their money, they circulated even longer and the ages stretched out. The US mint has done studies on this very thing. I even considered it for a dissertation, once.
I found a red, AU 1947 Wheat cent once in the playground. It couldnt've been there more than a few days. A 1945 Canadian cent? It could have floated around for a decade - or more - before it was dropped. As we say in this hobby, "You never know."