This is made by a company called Garelick. Around $200. Installation was easy, though required a second pair of hands. I reinforced on the inside, but after watching friends boarding I can see i need to strengthen the outside of the transom as well. The backing plates go vertically inside the lazarette, I figure some side-to-side pieces of teak or something on the outside would make it very solid.
It was leaps and bounds better than the single rung ladder that was on there when I bought it. Much easier to board for everyone and a convenient way for ladies to pee. I even put a little down-shining LED out above it for better footing at night (its not there in this picture)