There is a Univar in Tampa, but I doubt if you could buy less than a 15 gallon carboy (least expensive by far, though). One of their salesman might tell you where you can buy 2.5 liter lab grade (most expensive) or a lab supply that re-packages technical grade chemicals (cheaper but still expensive) into smaller quantities. Also, call around to companies listed under lab supplies.
http://www.univarusa.com/vwr-inc/facilities.nsf/cc6a7e5dabe2c72988256a93007ae39d/dc5b607bdceec0ba8825741a0061d350!OpenDocument
Although much more expensive, the 2.5 liter and 1 gallon sizes are safer to use. With larger amounts, you would have to transfer some to a smaller container when you need it. This can be quite dangerous if you don't know what you're doing.