Are you looking to duplicate what it would have come with? If you are handy you can make the inserts out of 1 inch white strofoam and ether flock it or cover it with stretch velvet/velour. That way you are just looking for an empty box which won't be as expensive. Just a thought, if you are not trying to make it look correct, you could use a six inch box if you found one also, and turn the gun so it isn't oriented straight across and it will fill it up and looks good as well.