BRIEF-Rig firm Seadrill sees $445 mln revenue from deal via Brazilian JV

OSLO, July 3 (Reuters) - Seadrill says: * Seadrill and Sapurakencana's pipe-laying support vessel starts Petrobras job * Says total revenue potential for the firm contract period is estimated at

US$445 million. * The contract is for a period of five years, with an extension option for an additional five years * The pipe-laying support vessel is owned by Sapura Navegacao Maritima, which is co-owned by Seadrill and Sapurakencana * This is the first of six units contracted with Petrobras under the joint venture (Reporting by Oslo newsroom)