After Churchill on your way to Moosonee make sure you have enough time to stop at York Factory and visit the historic site. It is a short flight from Churchill. It has been many years since I visited the old Hudson Bay Outpost but have always wanted to go back. Check out this link for more info. http://www.pc.gc.ca/eng/lhn-nhs/mb/york ... index.aspx
There used to be a small strip on an island. A local lodge operator provided boat transportation to the site. I'm sure with a little investigation in you could find out if that option still exists. Check out this link for more info. http://www.pc.gc.ca/eng/lhn-nhs/mb/york ... index.aspx
From York Factory fly the south shore of Hudson's Bay to see the Polar Bears. Make sure you check the CFS as there may be some restrictions on altitude for the protection of the bears. Again, it's been a lot of years but this was one of the largest concentrations of Polar Bears in Canada.