The VC Sidebar element might come in handy if you want to create complex sidebar layouts, but can also be used for repeatable content blocks. Create a new post under the VC Sidebar tab in the admin menu and start building your sidebar/block with the WPBakery Page Builder.

Add the VC Sidebar element to a post/page and select your sidebar/block which you want to display.

This element is also available as native WordPress widget under Appearance → Widgets