The 70-year-old, of Italian origin, stole the artefact from the site’s theatre during her honeymoon, Il Mattino reported.
Although she kept the relic close by, even taking it with her to Beijing when she lived there, the theft weighed on her mind for most of the next 50 years, the newspaper said.
“I regret what I’ve done and want to fix it,” she reportedly told heritage police in Naples, who returned the item to Pompeii.
The Canadian isn’t the only tourist to be overcome with guilt after misbehaving in Italy.
The mayor of Lerici, a town in the northern Italian region of Liguria, said he was pleasantly surprised in September when an American man paid a parking fine that, coincidentally, also dated back to 1964.
Robert Atherton, from Pheonix in Arizona, said he never got around to paying the 1,000 lire fine, handed down after he illegally parked his Vespa, due to forgetfulness.