Rakesh Raja

This plugin hide content in posts and pages and display only when a user leaves comment. If page/post dont have a comment from user or its got deleated by admin, content will be not displayed.
This plugin uses cookie for that so this plugin will work when user allow website to set cookie.
Restrict it provides you a shortcode [wpgrestrict][/wpgrestrict], wrap your content with this shortcode and you are done.
In next version, I am going to to add restrict content by logged in user. Please let me know if you need any other way to restrict content.
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Restrict It

Restrict content in posts and pages with this plugin and display only when a user leaves comment.

WP Chill

Awaken Solutions Inc.

This plugin allows you to easily mark certain pages with “Permissions” and only users with those permissions will be allowed to see the contents of the page.
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Page Permissions: This plugin adds a new Permissions taxonomy to your pages. Administrators can create/assign new permissions from the Edit Page screen (you can also use the Quick Edit link). You can add/edit/delete permissions from the Permissions sub-menu under the Pages menu. Pages with no assigned permissions can be seen by everyone.
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User Permissions: Administrators can add/remove permissions from a user using the checkboxes on the Edit User screen. The All Users page has a column that shows the permissions assigned to each user.
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Restriction Message: If a page has permissions assigned, the content will only be visible to users that have one of those same permissions assigned. Otherwise, the content will be replaced by a generic message or a custom message which can be defined in the plugin settings using the standard WordPress editor (including the ability to add media and formatting).
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Redirect to login: Instead of a restriction message, you can choose to have users get redirected to the login page.
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Simple Restrict

Restrict pages based on permissions assigned to pages and granted in user profiles.

Restrict It vs Simple Restrict