American Airlines has round-trip flights from Austin (AUS) to Pittsburgh, Destin, or Burbank (PIT, VPS, BUR) for $132-$157 with a connection. Flights November to December. No Sunday departures. Weekends available. Origin/Destination reversible. No Christmas dates available.
A Carry-on bag and also a personal item is allowed for free on American. You can avoid paying for seat selection by accepting the randomly assigned seat at the gate.