TORONTO, Nov 15 (Reuters) - Canada's main stock index rose on Friday to its highest in more than two years after Federal Reserve Vice Chair Janet Yellen, who is widely expected to take over as head of the U.S. central bank, expressed strong support for the Fed's stimulus program. The Toronto Stock Exchange's S&P/TSX composite index unofficially closed up 51.19 points, or 0.38 percent, at 13,482.57, after reaching 13,490.19, its highest since July 2011. Seven of the 10 main sectors on the index were higher.