United, ANA, and Delta have round-trip flights from Austin (AUS) to Tokyo (HND) for $744 with a connection. Flights in April, August, September, October, November, and December. Departures on Monday, Tuesday, Wednesday, and Sunday. Holiday blackouts.
These airlines have recently added late April fares.
Some of these April dates require minimum stays of about 10-day or more.
Some small OTAs on Skyscanner have this for as low as $728; which is cheaper than the airline. If you plan on booking there, beware of any site that charges a fee to cancel a ticket within the 24-hour “free” period. Use unknown booking sites at your own risk.