Don't buy phony plastic barrels - acquire the real thing.  Not only are these real half wine barrels, but after a complete sand, the barrels are treated with stain, sealer and at least two coats of varathane to create luster and make them last much longer than the old used planter barrels you see at most garden centers.  

These decorative-type planters are made from genuine oak wine barrels. The bands are colored (primed and painted). The barrel is approximately a foot-and-a-half tall and 27 to 28 inches wide.