BuyDig (99.1 % approval) is selling the Tamron SP 150-600mm f/5-6.3 VC for $699 (Reg $949) after two mail-in rebates that total $120 via ebay. If you're looking for the least expensive supertelephoto solution out there, act fast as quantities are limited.
BuyDig is an authorized Tamron dealer, so this is not a grey market item.
Tamron SP 150-600mm f/5-6.3 VC $699 (Reg $1069) | Rebate forms from Tamron USA