VANCOUVER, British Columbia , Sept 9 (Reuters) - A U.S. court has ruled that a case against Barrick Gold Corp. ABX.TO and J.P. Morgan Chase JPM.N alleging they conspired to manipulate the gold price can proceed to trial, court documents obtained on Tuesday show. A Louisiana district court judge ruled last Wednesday that the antitrust case brought by New Orleans-based coin and bullion dealer, Blanchard & Co., against the world's third-biggest gold producer and the U.S. financial services giant can go ahead. Blanchard alleged in a lawsuit filed in mid-December that Barrick and J.P. Morgan Chase made $2 billion in...