The hammer/staff thing? That shouldn't be too hard. The staff part could just be a wooden rod or staff, you wouldn't have to make that, I don't think.
And you could sculpt the upper part, the head out of styrofoam or some sort of foam. You would just have to be careful with what paint you use, since some types erode styrofoam.
Good luck! If I think of any more tips, I'll be sure to post.