I just found this on Cotton On's Ebay page. They have a bunch of items for $3.50 to $10 with free postage. It's mostly womens stuff, but there are lots of t-shirts, singlets and Spring/Summer wear.
Example Item: Cotton On Womens Curve Relaxed V Neck $19.99 $5 $4 with PLEAT20
Mod: Additional 20% off with PLEAT20
Original Coupon Deal
This bottle seems nice for $4 delivered with code PLEAT20 And it was $12.99