if you do have permit, the days you hold a valid permit will be counted as the days you stay in Canada. If the number of days taht you have hold a valid permit plus the days you stay in Canada after you landed is over 730, you have good chance to come back.
No maple card? apply for a travel document.
my suggestion: check the official web site of CIC or write to Canadian Consulate in US yourself. Any answer you get here can only be reference.