I don't know, I assumed by his "a local store here" that the guys there will let him choose, and they are willing to help him by providing a computer with internet access to verify the number.
Worst case scenario, take a paper and a pen, note the no., tell the guy "hold this for me for a few hours", go home, check the number, find out that the phone is from January 2012 (most likely with 5.0.1 of it), go out rejoicing, get drunk, forget to buy the phone...