I would buy a cheap plastic case and put the gun in it. Then get a cardboard box that it will fit in. You will have to go to the UPS Hub in your area, to send it. The retail stores (UPS) will not ship it. It can be shipped directly to him, and he can ship it directly back to you. That's the way it works in Wi. Hope this helps.
On a side note. I would call Rob and make sure this is the way to go. He will know..
Mike