I made this Samara costume this past Halloween for myself.
I purchased an old gown and black house shoes. I wanted something that looked old school and of course white. I also purchased the wig and tangled it up a lot. I placed white and beige makeup on my face and dabbed some liquid latex over the make up once it was dry. I also placed gray and black makeup under my eyes. I waited a few minutes until the latex was dry and used tweezers to rip the latex skin in different areas of my face (to appear as if I had been rotting in a well).
For the well, I purchased some plastic mesh from Home Depot along with some brick printed party paper. I made a large cylinder out of the mesh and wrapped the brick party paper around it. As you can see on the ride I got an old VHS (which I carried around the party with me) and wrote "7 Days" on it.