You need a valid PR card or PR Travel Document to return to Canada via plane. A week in the US may not give you enough time to get a PR Travel Document. If you don't have your PR card by the time you have to travel, recommend that on your return home, you fly to the nearest US city airport close to where you live and then you can re-enter Canada through a US/Canada land border using your COPR. You'll need to use a private vehicle to re-enter Canada or do so on foot (no bus).