For 1968 dimes there are no known Doubled Die Obverse or Doubled Die Reverse examples that I am aware of. I'm not sure if there have been any found for 1960 through to 1969 in general.
i have actively been hunting down genuine doubled die examples for each denomination of Canadian coins and the coins from the 60's only seems to show doubled dies on the pennies and 1$ coins.
As for your coin, better photos are needed to determine if any kind of doubling is present.
Finding and discovering modern Canadian doubled die varieties since 2018.
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Modern Canadian Doubled Die Varieties - First Edition
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