If you are coming for 2 weeks, just use your US license, perfectly valid. I got my first BZ license 6 years ago in SP, although the test was easy, it took longer than your vacation to get them to schedule it! It was about 25 questions, they X out things like what side of Albert Street do you park on? Funny!
You don't need one until you move here permanently and don't want to go back to the US just for a license.