Kind of a great shame there is a large expanse of water between us, otherwise if you lived in the next street, I could have looked, then shaped. I have a lathe, milling machine, welding gear, and lots of hand tools as well. In fact could have made what you want from scratch probably, and due to the fun of such a project, it would only have cost you a few beers in the local bar.
However, if pictures were provided, and a rough sketch of what you have in mind as a finished job, I am sure advice will be forthcoming.