Sorry, when you write “chaos dwarf” magic items, I took that as “chaos dwarf only” kinds of items. You’ll have to check the specific listing (which I don’t have in front of me since I’m at work) but if it says a hobgoblin can take ‘x’ points of magic items, they can choose from common magic items as well as those listed in the army book. But not the items that are “chaos dwarf only” of course :cheers
In RH, Hobgoblin Heroes can use any of the army list items and common items that aren’t restricted by saying “Chaos dwarfs only”, or that are over their points limit, or that they wouldn’t be allowed due to the item type (can’t carry a magic banner because they can’t be a BSB).