If you don't have everything, maybe you could pick up a handful of pieces that seem most interesting/useful to you, to try and get the most out of the class.
also, there's a lot of similarities in the types of stamps. Maybe if you don't have the exact stamp listed, but have a similar style/type, you could substitute it, to work on the technique, even if its not the exact stamp. If you show up with "most" of the stuff, he "might" have a few extra tools, and he might let you borrower one. I wouldn't bank on it, but if you get in the class, and they are working with a tool you don't have, it doesn't hurt to ask, and say that a tool you haven't bought yet. -just a few thoughts.