Large ammo shipment =
(Me) 10,000 rounds or more
(Feds) More than one box
Also, a C&R runs $35, not $300. I recommend you get one now before the ATF does away with them. I've never bought a C&R gun, but I use mine to get the dealer discount at Midway and Brownell's.
I also believe that if you sent a gun in for service, say to Springfield, they can send the gun directly back to you. Don't quote me, but I think that's right.