Drumco in bauxite sells plastic drums of all sizes I think. You may want to call them to see what they have and prices on them. I know they sell new and refurbished plastic drums.
smallest they show is a 30... but thanks for the headsup heres a link for those interested... http://www.drumco.com/index.html
here is a site i have considered getting a couple from. they have food grade barrels, new and refurbished. They come in small sizes too like you are looking for. http://www.bayteccontainers.com/waterbarrels.html
what are you needing the barrels for if need for water for water c/o you can go to wal-mart and in the sporting goods and get the blue jugs for I think $9? and there 7 gallons just a thought
im using the barrels in the living room for top off.. i wanted the small 15 gallon barrels to enclose in a cabinet to hide ( so wife will let me live) i have the 7gallon containers already.. i talked her into the 30gallon barrel in the living room (temporarily) lets see how long temp exactly is