I think there are no braille examples for the sidebars because they aren't necessary. "Sidebar" is a new term in Formats and the braille format is very well described. Simply braille the sidebar as boxed material, using the appropriate paragraph format as in print, and place the material in the appropriate location as determined by how the material relates to the regular text. The commentary in the section clearly explains that the purpose of the section is to identify sidebars so that the transcriber will know which print material to treat in this fashion. Several types of print sidebars are shown. If a transcriber is uncertain about how to place material in a box, I recommend a visit over to Section 7 Boxed Material.