By Tom Westbrook SINGAPORE (Reuters) – Japanese markets were reeling on Friday, with the Nikkei heading for its biggest weekly drop since October, bonds battered and the yen surging toward its largest weekly gain for five months as investors rushed out of bets on Japanese rates staying low. Beyond Japan MSCI’s broadest index of Asia-Pacific shares ex Japan rose 0.5% and Treasuries sold slightly. The Nikkei was down 1.6% for a weekly drop of 3.3%. [.T] Other moves were more modest as traders wait on U.S. labour data due later in the day. The yen leapt more than 2% on Thursday and was well suppo…