Bose QC35 II Black/Silver are on sale at $299.99 on almost all merchants.
Best seems to be at Crutchfield.com because of no tax. They also offer 60 day price-match.
Alternatively Abt.com also has them for $299.00. You can combine it with Discover CB deal for 5% off. Has tax in 4 states though - IL, MI, IN, WI.