With the Bachmann 3-truck Ho scale Climax out, why not make a Ferdinand model from Thomas Misty Island Rescue. It shouldn't be too hard, just change the valve gear from Walscherts to Stevenson give it color and add a face and change the couplers. It might be the most expensive Thomas model in HO since it has more realistic details than the others if the spectrum is to be used. But it would be a good start. I would love to see Ferdinand the Climax in HO scale.
It would be cheaper to tool up a new mould and mech for moving eyes
As cool as that would be, Bachmann usually creates their Thomas and Friends models from scratch, rather than modifying a previously released model. However, that definitely sounds like a good D.I.Y. project!