Using the method described in the OP, I have gotten two oranges so far. Just one difference. Instead of creating a new save file, I've just been using my existing Sam B, who is level 50. I tried the new save file method a few times and didn't get anything, trying for over 30 minutes. But by using my existing level 50 character, I have gotten an orange item in about 30 minutes each time.
I think the level of your character plays into it. a level 50 character is a little more likely to get an orange than a level 30. Other gamers have stated this on another site where we were discussing this same achievement.