All the short ones that fit over trail shoes aren't waterproof, just debris proof. I ended up sewing some elastic with a cordloc to the bottom edges of my waterproof trousers with the hook from a trouser hook and eye set on the front bottom edge of my waterproof trousers, which could be hooked over the shoe laces, gaiter style, so that the trouser became a gaiter for a weight penalty of about 10g. Obviously this only really makes sense if your waterproof trousers have elasticated bottoms. If they are wide they will protect the top of the shoes anyway.
Those montbell ones look good though.