Boy, I wish the was something in my wheelhouse, I would do it in a heartbeat!
JustG, apologies didn't see your post sooner.
Unfortunately living where I do, the cost of materials, shipping etc would probably make these cost prohibitive. I would hazard a guess that even the shipping costs for something like that from where I live, would outstrip the costs of just having a local fabrication shop make one for ya. I bet they could make you one up for a couple of hundred dollars US.