MONTREAL – Bell Canada is buying national consumer electronics retailer The Source, the companies announced Monday. While the purchase price was not released, Bell said it would be "materially less" than the $335 million paid for the chain by Circuit City in 2004. (The Source was once Radio Shack in Canada but was forced to drop the name in a branding dispute prior to its sale to the now-bankrupt Circuit City.)The 750 Source stores will offer the full array of Bell consumer services - including Bell home phone products, Bell Mobility, Solo Mobile, potentially Virgin Mobile wireless products and services, Bell TV,...