No. 

You can use some dual wield weapons for parrying. But dual wielding is primarily useful for PvP-badassery.  
No parrying weapons are as good at soaking up damage as a high spec shield. And it's easier to block than to parry, requiring far less precision in terms of timing.

Not true at all.  Totally based on the weapon you are off handing.  For example the Large Sword of Moonlight has the highest magic block power in the game second only to the Dark Silver Shield.  Kilij's can parry, most straight swords can block, most large swords block, etc etc.  However if blocking is your thing you are almost always better off with a shield.  The best parrying weapon in the game is actually the parrying dagger, it has an extra long animation.