tiddy is incorrect about the "N7" weapons (they are very confusingly named, unfortunately): The promotional N7 weapons -- the Valiant, Hurricane, Eagle, and Crusader -- are distinct from the Ultra-Rares (despite the latter also having an N7 badge) and will not be granted by Spectre or Premium Spectre packs, even as upgrades. They also appear in a different section of the Multiplayer Manifest on your account on social.bioware.com.
You can only get upgrades to the N7 promotional weapons from Victory/Commendation packs, you cannot get them via any other method. For example, if you have level I of each of Valiant, Hurricane, Eagle, and Crusader, then the next Commendation Pack you receive will upgrade one of those weapons to II.
If you got really, really lucky with your VPs the highest level you could currently have of any of the N7 weapons (again, the Valiant, Hurricane, Eagle, and Crusader) would be VI, if you had received the same weapon every time (very unlikely).