Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from St. John's to Galway as you normally would.
St John's (YYT), located 6.7 km from the city centre, is the airport you fly out of when you book flights from St. John's to Galway. 1 airline have flights from St John's to Galway on a regular basis. Booking flights from St John's to Galway should not be difficult; the airport handles an average of 0 outbound flights to Galway per day.