It depends on airport and film speed.
Some airports allow manual checking (sorry, I don't know about SEA) but you should reckon on the film being x-rayed anyway.
What speed is your film? Up to 400 ASA should be OK for one or two passes. Higher than that, I'd be worried. Will you be able to process the film while you're away? That would cut down on the risk.
And no, it's not retro - you're an artist!