I'm not sure how much legal ground you've got there. The model is wood, so it's hand sculpted and painted, making it their original artwork of your design.
Whereas the guys that 137th Gebirg was talking about, were selling his artwork.
Well the company that has listed my designs has contacted me with an offer for the use of my designs. I am currently thinking it over and may send a counter to see what they say. I am trying to decide what I want to do, but they have contacted me.