Canada and your transaction is processed by a payment gateway located in the United States, then your personal information used in completing that transaction may be subject to disclosure under United States legislation, including the Patriot Act.
Therefore, you should do your best to avoid using legal terminology where possible. Possible legal bases are individual consent, the performance of a contract, and your legitimate interests.
Privacy Policies from real businesses.
They also include a summary of the most important points at the very top of the page.