TOKYO, March 31 : A few dozen tourists hopped onto a small cruise boat in Tokyo to admire the cherry blossoms lining the Meguro River - a seasonal attraction that could soon become costlier for passengers and operators alike. The pink and white flowers that blossom in spring on cherry trees across Japan are a major draw for locals and tourists - and big business for companies such as cruise operator Tokyo Waterways. The "flower viewing" or "hanami" is the peak season of the year. This year,