There are 423 object models in total (00-1A6). The Japanese version only goes up to 409 (199) although the Australian version goes all the way up to 452 (1C4). Both of them rearranged the object models in their respective versions.
All objects will be covered regardless if they are used or not (for Australian only unique models). Not all objects might have images, but we are working hard (with breaks) on adding them.
There are some more things to take into account, but we'll get to them eventually.