If you're buying new tree huggers, beware. They're very expensive in some places. Strapworks rocks.
6' long polyester with a loop on each end - $6.27
6' long polyester with a double d-ring on each end - $6.65
bonus: you can get the d-ring straps with puppies or flowers or ponies on them!
Shipping in a US Postal Priority Mail box is a whopping $5.80. You can get one heck of a lot of straps in one of those boxes.