Anyone know where to get a metal storage box that will fit in the back between the wheel wells? Looking online with no luck.

 

http://www.truckbox.com/
There are others. Try search terms like; jeep cargo box, SUV storage, interior cargo box.

 

You could also look at job site tool box manufacturers like jobox, greenlee, knack companies like that I know the last job I was on there were a bunch of small jobox there that would have been perfect for the back