TORONTO — Two of Canada’s biggest private-sector labour unions are formally exploring the possibility of creating a new, merged organization, a move they believe could spark other unions to join them. The Canadian Auto Workers and the Communications, Energy and Paperworkers, which have a total of more than 320,000 members, said Tuesday they have been holding preliminary discussions for weeks. CAW president Ken Lewenza said the move comes as a response to the “incredibly hostile economic environment” its members face and will give the unions a better stance against a “confident employer base” and Canada’s majority Conservative government. “We have…