You can grab a bike boz from any lbs then just toss it or stash it when you land and repeat when you fly back. You can wrap it in a plastic bag with foam pool noodles. I grabbed a zip up bag off wiggle a couple years ago for like a hundred bucks and have had no issues with it, though I've always had to pay oversize with it, my friend managed to sneak by with it once. Trash also makes a fly bag that's not exactly cheap buy looks very functional for people who want to ride to/from the airport.