My current tub is 3.1 oz. I've gotten it in other sizes over the years - 3.3 oz, 4.5 oz, 5 oz.
A 3.1/3.3 oz tub should be around $30 including shipping on ebay. That will last me well over a year so it ends up being pretty darn cheap.
The ingredients aren't printed on the tub and I didn't keep the box. It's basically palm oil, a couple other plant extracts, and fragrance.
I love love love the scent so I always buy the original formula and not the new 'lighter scent' Plus formula.