Is this a first when consumer product company releases CAD geometry for their parts?

Suppose I would like to produce a modified replacement plastic part for my phone; how much would that cost? For starters, a different color interchangeable panel for a phone with interchangeable panel, such as Lumia 435 or Xperia U http://www.gsmarena.com/sony_xperia_u-4437.php but, eventually, an extended size battery and a cover for it.