Mammoth Uncensored Word List:
24 words ending with oo, 8 letters long

ballyhoo buckaroo buckeroo callaloo cockapoo cockatoo gardyloo gillaroo hallaloo hubbuboo jackaroo jackeroo jillaroo jordeloo junkanoo kangaroo peekaboo peekapoo rubbaboo superloo vindaloo wallaroo wanderoo waterloo