You could ask for a phone whose manufacturing week is less than 45. ( which can be verified by the serial Number.) I wonder if apple stores will stock phones with less than 45 weeks manufacturing. You could try other sources besides apple as well. In the worst case apple iPhones are also available in Qatar except that they are slightly (or very) costly.
As far as unlocking the phone is concerned have no worry. Dandy here seems to be an expert at it. Still if you have any problems unlocking let me know, I will do it for you and if required teach you how to do it. (without any deal.)