I would be real surprised to hear that a manufacturer made a kit like this. I don't think there would be enough interest to warrant it. Sounds like time for some scratchbuilding.
You might be able to kit-bash something with the DPM or Walthers modular sections, or maybe start with the front of Carr's Parts. DPM has the template pack you can download from their site - I think - so you can make a mock-up to see if it will work.