most items in the game have a 1 and only 1 unique version that can drop from a monster. If you type in Herald Of Zakarum into google you'll most likely find a site that tells you all the little details about the item, including the type of item it is. In this case, the "normal" version of HoZ is Gilded Shield. One level up and you have Zakarum Shield.
uping a hoz isnt always a good idea
it wont gain alot of def, and its req str will be 142 (was 89)
169 x (1+ed/100) = hoz 422~507
(169~193)x (1+ed/100) = up'd hoz 422~579