Same Problem but Apple sorted it out for me!
I had exactly the same problem, bought a full price 64GB 3G and didn't pay for a SIM.
It was locked to orange.
Made a genius appointment and it took me a good 40 minutes but eventually a manager simply gave me a brand new unlocked iPad.
I was amazed and did not expect that.
I'd strongly suggest you travel however many hours to your nearest apple store and make an appointment and see what happens. There is no guarantee that you will get a new iPad but it's worth a try! Good luck.
Biting the hand that feeds IT
