Support

No, that's not possible. This has to do with the fact that Joomla! doesn't have a single URL scheme, meaning that one page can be accessible for multiple URLs. For instance, all of the following could lead to the same page:
http://www.example.com/index.php?option=com_foobar&id=15&Itemid=7
http://www.example.com/index.php?Itemid=7
http://www.example.com/foobars/1-some-category/15-my-item-alias
http://www.example.com/foobars/1-some-category/15-my-item-alias.html
http://www.example.com/foobars/1-some-category/15-fake-the-alias-it-still-works
http://www.example.com/foobars/you/dont/say/this/still/works/15-my-item-alias
http://www.example.com/foobars/you/dont/say/this/still/works/15-even-that-would-work
http://www.example.com/foobars/15

It all has to do with how Joomla! expands URLs internally and how each component's router works. Add a SEF component and it gets even worse. Therefore it's impossible to positively and indisputably identify a specific page in a unique way. And that's exactly what makes per-page features impossible to create, at least in a way that's user friendly and watertight.

This is still not possible. Besides, Geographic Blocking is as good as no blocking. Do you know what I'm doing when I can't access a site? I find a free proxy server on the country which is allowed to access the site and use it. The only reason I have GeoBlocking in there is that there are people who don't want to hear me when I tell them how pointless that is. Creating a very complex feature where you would see the entire country / continent list for individual URLs (bad UI) and have the Admin Tools plugin check if each URL being accessed appears on that list of URLs (slows down the site) is out of the question. It would create a bad interface, slow down the site unnecessarily and lead to increased support requests from people who don't understand that content in Joomla! can have multiple URLs. All that for a form of protection that's trivial to work around. No, that's clearly a waste of time.