Prevent output from get_sidebar() without altering core files

I am trying to replace the output of get_sidebar() with that of my own function.

I know I can tie into the “get_sidebar” hook, which is executed at the beginning of the get_sidebar() function, in order to alter the output. However, after that filter hook is executed, the rest of the get_sidebar() function still runs, and loads a sidebar (which I want to avoid).

I guess my question is, after tying into this hook and generating some custom output, is there any way to prevent the rest of the function from running, or limit its output in any way?

Here is a link to the contents of get_sidebar(), where you can see the sequence of the hook with respect to the original function.

get_sidebar() function

Any help is appreciated!