Will you be travelling to the States under the visa waiver program, or do you have a visa?
Note that the visa waiver program normally requires you to have a return ticket or an onward flight that does not terminate in Canada or Mexico.
However:
"Citizens of VWP countries* who reside in Mexico, Canada, or a nearby island are generally exempted from the requirement to show onward travel to another country* when entering the United States."
https://travel.state.gov/content/travel/en/us-visas/tourism-visit/visa-waiver-program.html
So, in your case, you will have the issue of proving to US customs that you are a PR of Canada because you do not have a valid PR card. And if you don't have another way of showing that you will leave the US within 90 days, you may face difficulties.
In practice, you may never be asked, and it's up to you if that's a risk you want to take. But it would probably still be best to book a return flight or an onward ticket that does not terminate in Canada or Mexico.