Can I disable channels in Redactor "Link to entry" feature? I have some channels with entries that I don't want my client to be able to link to using Redactors "Link to entry" feature. Can I disable some channels for a specific field in a specific channel/structure/single?
Here is a super hacky way to do this...but it does do the trick. 


Locate the JS file responsible for rendering the Element Selector Modal (craft/app/resources/js/compressed/RichTextInput.js)
Search for: {storageKey:"RichTextFieldType.LinkToEntry". This is where the modal gets called. 
Nearby, locate "criteria" and change 

{locale:this.elementLocale} to {locale:this.elementLocale, section: ['sectionYouWant','otherSectionYouWant']}
Push this JS file to your server and only the sections you include in the section array above will show entries. The other section titles will show, but no entries will show up to select.


Keep in mind that this adjustment will probably be overriden by any Craft update. I bet building your own redactor plugin would be cleaner.