KingSize Direct offers the Boulder Creek Men's Long Sleeve Sportsman Shirt in four colors (Gulf Blue pictured) for $29.99. Coupon code "KS62811" cuts it to $23.99. With $7.99 shipping, that's $11 below list price and the lowest total price we could find. It is available in sizes XL and 2XL, but not all color/size combinations. Deal ends December 2.
Note that sizes 3XL, 4XL, and 5XL are available for an additional $4 and sizes 6XL, 7XL, and 8XL for $8 more.