If you call a local bike shop they would be more than happy to set a box aside for you. Take a multi-tool and a crescent wrench to remove the pedals and shove the thing in the box with some padding and tape it up with some clear plastic tape and either ship it or throw it on the plane. Explain what you are trying to do to the bike shop and they will save all of the packing crap that comes with a new bicycle which will make it easy to pack this one up.