You'll need to check the serial number before purchasing. The 4th & 5th digits correspond to the production week. From what I have seen:
Week 44 -> software 1.1.1
Week 45 -> software 1.1.2
Week 46 -> software 1.1.2
So try to get one from week 44 or earlier. This will be your best chance of getting software 1.1.1.