Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Thunder Bay to Bangkok as you normally would.
Thunder Bay (YQT) is the airport you will fly out of if you book a flight from Thunder Bay to Bangkok. You should not have trouble finding flights to Bangkok from Thunder Bay; the airport handles an average of 0 outbound flights to Bangkok per day. You should also have plenty of airline options to choose from since 2 airlines have flights from the Thunder Bay airport to Bangkok. It is only a 5.6 km journey to Thunder Bay (YQT) from Thunder Bay’s city centre.