Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Indianapolis to Kyoto as you normally would.
Due to multiple factors, expect to potentially pay more when booking in October. For low rates, June can be a great choice for travel to Kyoto. Flights to Kyoto from Indianapolis in June are about $1,218 on average during June, but can be found for as low as $840.