Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Malaysia to Galway as you normally would.
Yes, there are multiple flights from Malaysia to Galway for under RM 2,900. The cheapest flight booked recently is on Multiple Airlines for just RM 2,829, but on average you can expect to pay RM 3,473.
On average you can expect to pay RM 4,294 for a flight from Malaysia to Galway. The cheapest flight overall is RM 4,294 while the most popular route, (Kuala Lumpur Intl - Shannon) is currently priced at RM 2,829.