We have received a good news today by Tamron USA, Tamron will start selling its Tamron 150-600mm F5-6.3 Di VC USD SP Lens lens from January 17, 201 in USA, the lens was announced on November 2013 and also available in Japan from December 19, 2013. Suggested retail price 140,000 (147,000 yen including tax) Approx $1351.00 in USA.
See Tamron 150-600mm F5-6.3 Di VC USD SP Lens Press Release