My general question is, are some sets rarer than others? If so, which ones and how do you all go about procuring them?

My more specific question regards the Juggernaut set (http://elderscrollsonline.wiki.fextralife.com/Juggernaut+Set). Has anyone found a complete set of this yet? A little while back I picked up 3 level 30 pieces of it (chest, shoulders, and pants) from the unknown armor vendor in Cyrodiil. As an Argonian Nightblade tank, I fell in love with the idea of using this set for PvE and PvP. But, I haven’t been able to get the rest of the set (helm and shield) or find a single person who has found them either. I know the set comes at level 30 and VR1 (or higher?), so I have been trying to piece together a set for when I hit VR but no luck. It seems there is very little info on the set out there compared to other sets (I only found one site suggesting the last 2 pieces are helm and shield, so I’m not even 100% sure about that), so any input from you all would be appreciated!