roors are usually $150 to $200... i have seen glass on glass peices that use the same principal for less money, a friend of mine has one, and it hits very well...
I figure if you have the loot, buy quality... a fool pays little to buy something many times, a smart man spends much to buy something once. (or something like that...haha.)
as for where to buy em, most head shops, at least in my area, have them.. but my best experience has been with everybodydoesit.com... original german roors, competative pricing, the option to customize the roor, and out of 3 that i've ordered, 2 came within a week of being shipped, and the other was held in customs for 2 weeks, but was released... of all my purchases (i've gotten bowls and stuff from there too, ) I think i have a 6:1 success ratio, and the 1 time was jsut a delay really...