List of 2013 US National Merit Scholars
Using Google-Fu, I believe I have found what you are looking for:

The 2012-2013 Annual Report

As a guide, someone somewhere will always want to archive something. In this case, archive.org didn't have it, but the owner of that domain, who is likely to be an awesome person in research in a few years, cached a copy of it for us.

The statement used to find this document was:

"2012-13" national merit scholar annual report pdf

It is important to use the years in quotes as 2013 can be used to find the current report as well.