A long time before Steam integration, Catchy and Anton did this: http://forums.keenswh.com/post/catchys-custom-cargo-ships-6851828?highlight=catchy+cargo&trail=15 I don't think it's updated any more, but it's a shame because they had something like 15-30 small and medium sized ships, there was a nice selection. Maybe if you contact them they will give you the ships to use. It would be nice to see them flying again!