Hehe....
I thought if this. Its not hard to do at all. There is a couple companies out there that form moulds from existing cast parts. Mainly from decorative parts on historic buildings. Anyway, they make a sand mould much like they did years ago and then can cast several at once. The cost is not too bad and they can do small runs.
Then all you do is take the Dremel to it and drill, smooth, etc.
I think it would be very doable and not too cost prohibitive. But a minimum run would be best....