Ohh slickdeals dont you dare by sour!
FYE currently has a bogo sale using coupon code #100 . New Day tshirts are $7.88 each plus $7.49 standard shipping so buying two shirts comes to $15.37 shipped or even cheaper with backstage pass. All sizes are currently available however the red shirt says orders are expected to ship in December.
The tshirts can be found here and here (no small or medium)