How do I get the position of a single axis on a 3-dimensional plot?

I am trying to set the position of a colorbar so that it has the same vertical position and height of the vertical axis on my 3-dimensional plot. I can't use get(gca,'pos'), because that returns the position and height of the entire plot area, which is different from the position and height of the vertical axis because it's a 3-dimensional view, as you can see in the screenshot below.

In that image, the vertical position and height of the colorbar are set using get(gca,'pos'). How do I get the position and height of just the vertical axis, and not the entire plot area?