you definitely need to have 14 champions to cover the bans and other players picks, aside from that the only requirement is level 30. My advice is to get to at least 300 or so normal wins before heading into ranked otherwise you really cant expect to compete at the same level as some of the other players
this is technically the same for all australian imports on games that have been banned or unrated. its considered a contraband item. I'm assuming the same sort of law applies although australian customs usually doesnt give a shit about it.