I thought that if Mt. Lion was on SuperDuper that meant it was also on my hard drive since that's how I got it onto my external drive in the first place just like Mavericks.
I'll guess that you first cloned Mt. Lion to a partition on your external, then you installed Mavericks,
which overwrote Mt. Lion on your internal, i.e. your Mt. Lion volume morphed into your Mavericks volume, and finally, you cloned Mavericks to another partition on your external, which could explain, but isn't necessarily why you've got Mt. Lion and Mavericks on your external, but only Mavericks on your internal.
As I said earlier, every volume on every drive shows up in SD!'s pane, so if it ain't there, you ain't got it.
OK,
here is a visual 1, 2, 3.
The shot of Disk Utility is to make sure you understand to erase not the top item, but the one immediately beneath it on your internal drive. (I guess it will be named "Mavericks", but it may be "Macintosh Hard Drive", "Untitled"...whatever.) Note that the "Erase" pane gives you the option to change the volume's name, so if you like, you can change it to something uniquely recognizable for the moment; you can always rename it later.
The top SD! shot shows your sources, and as you can see, each one's location is identified by its icon...Mac HD for internal volumes and USB for externals in my instance...maybe FireWire in yours.
Select "Mavericks" on your external as your source.
The middle shot shows your destinations, with their locations also identifiable by their icons.
Select "Edgar" (the volume you just renamed) on your internal as your destination.
The bottom shot shows something similar to what you should see (unless you external is FireWire, in which case you'll see a FW icon on the left).
Click on "Copy Now".
After SD! has done its thing, navigate to System Prefs > Startup Disk and select "Edgar".
Shut down your MBP.
Disconnect your external.
Start up your MBP.
If all went according to plan, your MBP should start up in Mavericks.
