Custom sidebar

This theme has allowed me to customize a great deal, but I don’t see how I can fix the following. I’m trying to show a custom sidebar on a single page.

Normally, my pages don’t show my sidebar. Only my homepage does. I’ve found the Blocky Page Settings that allow me to override this for a specific page by enabling the sidebar. But on that page, I’d like to show a custom sidebar – not the standard sidebar I display on my homepage.

Is this possible in this theme?

The page I need help with: [log in to see the link]