The old Xbox Community Day 2013 Shift Code with the extra rare Maya "Closing Time" head and accompanying "Last Call" skin (and 5 keys) are now available again in BL2. This code was deactivated a while back and I searched wide and far for a Gibbed code for this head/skin set, to no avail. I ran across this code recently and it still works. There are no gibbed codes for this set - as far as I know.
Maya Community Day 2013 Skin + 5 Keys for Borderlands 2
I've only tried it on Xbox One - not sure if it still works for 360.