iPhone SE third generation on refurbished iphone?

These are users helping users forums, so nobody here has any knowledge of the status of any devices in the Apple Store or Refurbished online store. All you can do is check the refurbished store regularly.

The Canada Apple refurbished store will only ever have models sold originally as new units in Canada, and the USA store will only ever have USA models.

The current iPhone SE model A2275 is the same model in Canada and the USA.

iPhone - View countries with supported LTE networks - Apple (TJ)

There will always be refurbished phones, although it could be for replacement devices or for retail sales. There's really no way of knowing as it's a specific business decision where the stock of refurbished devices goes.