Actually chaotic soul has a right hand sidebar, not left.
You would need to hack the underlying theme files to add a second sidebar, and we do not have access to those.
What you would have to do is start with a theme that has both a left and right sidebar and then you can stylize that theme to look very similar to chaotic soul (if you have CSS editing experience).
The best way, if you are good with CSS is to start with Sandbox since it has a lot more capability and is highly customizable. There are a good number of CSS skins out there for Sandbox, and you might even be able to find one that gets you close to what you want so that you would not have to start from ground zero.
Since there is no official support for the CSS upgrade, and few here in the forums with much CSS experience, you should figure that you are on your own. Before buying the upgrade, you can go to appearance > edit CSS and wordpress has provided a preview function where you can try out changes before you buy the upgrade.