Very small boat (fine for our 3 year old) which is great fun. As it is small, it is light so it won't eat into your baggage allowance very much at all.
Blow up the inside of the boat first (it's hard to get your mouth around it if you blow up the outside first). There's a valve to blow up the boat floor and another to blow up the remainder of the boat. It only takes about half a breath to blow up the former and 5 breaths to do the latter - it's easy. Therefore I have to say you don't need a pump to blow it up.