iPhone 7/7 plus custom 3D/CAD designs for the use of 3D printing and case manufacturing

We require someone to provide us with a 3d model for the case of iphone 7 and 7s. designs is very simple overall but there is a slight change at the bottom of the iphone 7 Case , so it won't take much effort. we need a model made by any kind of software that would easily be used by manufacturing or a 3D machine to print out, we need to be in contact with designer for quite a time even after the design is given because the designs might change a bit (in terms of millimeter from the bottom side of the cover design). further details will be explained in the chat box.