What parks OP? As a lot of people said, crown land is a good option, and a lot of national parks back onto provincial parks, which are tending to open earlier. You also may be able to find a private campground nearby.
Side note, I am absolutely exploiting this virus to go to Banff in the late summer. Cheap car rentals, cheap canoe rentals, cheap gas, and most importantly, no busloads of Chinese tourists clogging up the popular spots, and less hikers everywhere else. The place is normally way too choked most years.
