CANADA STOCKS-Railways and financials nudge TSX higher in quiet trade

* Index up 7.85 points, or 0.05 percent, at 15,214.96 * Trading muted by U.S. holiday (Adds investor comment, updates prices to close) By Alastair Sharp TORONTO, July 4 (Reuters) - Canada's main stock index closed flat on Friday, but not far from its record high, as bank, insurer and railroad shares benefited from the likelihood of stronger economic growth in North America. Rising government debt yields also helped the financial stocks. With Wall Street closed for the U.S.