How do I change the draw rectangle of a sprite?

Just to preface, I'm using the 2D settings of Unity 4.3.4f1 and using C#.

I want to make a timer in the background of my current project where there are two sprites, the one in the back showing the 'run-out' timer and the one on top showing full time. I don't want a solid color, so I need two textures. The two textures would be very similar, so deforming the sprites would be very obvious. Also, since it will

In XNA I could specify what area of the image I wanted to draw, so by decrementing the size of the draw rectangle I could change how the texture would draw. I've been searching, but haven't seen anything similar in Unity. Is there a way to only display a portion of a texture?