South Korean stocks pulled off a rebound Monday from bargain hunting by institutions and private investors who shrugged off geopolitical uncertainties triggered by the Crimean referendum. The South Korean won gained against the U.S. dollar. The benchmark Korea Composite Stock Price Index (KOSPI) moved up with the start of trading and ended the day at 1,927.53, gaining 0.40 percent, or 7.63 points, from Friday's close