Black Rubber maid horse tank is a good idea. It's deep enough to accommodate a tall person. They ARE very very heavy compared to the other stock tanks. Henceforth why it is cost prohibited to ship them!
Tractor Supply and Farm and Fleet carry them. These stores are usually in every town or on the outskirts.
It's this one: 100 gallons.
The black actually will help keep the water warm in hot weather. Which is why I don't use them for my horses!!
http://www.tractorsupply.com/en/store/search/stock-tanks