IMHO, that would make the character no longer a Pure Mortal. Pure Mortals get the +2 Refresh as a compensation for taking no Powers. I admit, there is no book Template that easily fits this character concept, but by taking a Power, like an Item of Power, a Pure Mortal has to forfeit the +2 Refresh they get for playing a Pure Mortal. However, you're the GM and final arbeiter of what is allowed in your game. If it doesn't bother you or your group, it's not wrong for your game.
You could make a new template or have it covered under Minor Talent or Focused Practitioner, but it doesn't fit the letter of either.