Serious answer:
There's no way to directly convert between a case insert and a folded cardboard box. The covers here are all adaptations. They're missing three out of four box sides altogether, and that can't be recovered from what's left. The elements that remain are cropped or rearranged to fit a different set of dimensions. Often, new elements were also added, to help collections look uniform. All of this modification was done painstakingly by hand, not converted via some simple, automated method. The best you could do with the covers here would be to find a template for the type of box you want and rearrange all of the elements by hand, same as how the covers were made. You should be able to make a box that looks decent on your shelf that way, but it absolutely won't be the same as the original. If you're serious about doing this for yourself and not to sell counterfeit games or boxes, then that should be okay, right?