GM Korea Co., the South Korean unit of U.S. automaker General Motors Co., said Tuesday that its sales in September rose 10.2 percent from a year earlier on solid consumer demand. GM Korea sold 65,541 vehicles last month, compared with 59,470 units tallied for the same month in 2010, the company said in a statement. The figure also represents a gain of 20.4 percent from 54,444 units sold in August.