Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Exeter to Whistler as you normally would.
Exeter (EXT) is the airport you will fly out of if you book a flight from Exeter to Whistler. You should not have trouble finding flights to Whistler from Exeter; the airport handles an average of 0 outbound flights to Whistler per day. You should also have plenty of airline options to choose from since 0 airlines have flights from the Exeter airport to Whistler. It is only a 5.3 mi journey to Exeter (EXT) from Exeter’s city center.