While it's more effort than I'd be prepared to go to, there is nothing stopping you storing the encrypted backup of your iPhone on the server/service of your ch

While it's more effort than I'd be prepared to go to, there is nothing stopping you storing the encrypted backup of your iPhone on the server/service of your choice, then pulling from said server location to restore via iTunes upon arrival. You don't need to keep the encrypted backup stored locally on the laptop you take with you through customs.