High lumber prices in North America are back, even as the industry steps into what is normally a seasonal lull.  Prices are climbing amid tight supplies and a pickup in homebuilding. Western Canada is seeing reduced output and the U.S. South is grappling with labor shortages. The U.S. is also expected to double duties on a common Canadian wood next month, adding to costs.  The rise signals that homebuyers will face elevated prices for longer. On Oct. 26, lumber futures were trading around $735.70 per 1,000 board feet in Chicago ...