I know im a little late on this one, but if its a bird for work, and you dont want a noisy one, i would suggest Finches. They are small and can get plenty of exercise in their cage, and they arent very loud. A cockatiel makes a great pet but they need a lot of attention and should be taken out for exercise.
I guess it depends on how much time you are willing to devote to the bird, but Finches are more an ornamental pet, they are beautiful and do not require the constant attention that most birds will demand of you.
Just a thought, but check out the Zebra finches or Society finches, they are inexpensive and quite a beautiful bird.