Let's see here.... *rubs hands together* For teeth, check out this thread
. There should be some useful links within it. For the hair, I think you've got the right idea. I don't have any experience or much knowledge of that type of wig-styling, so I would search out cosplayers who have made characters such as Sora, Cloud, Yugi, etc. or any character with "that type" of hairstyle. I think they usually use shoulder length wigs, or longer ones that can be trimmed down. This wig
might work pretty well for him.
I know that probably wasn't much help, but I tried!! ^.^