Dreadnaught Armor (Tier 3)

[Dragonlord567]

Where can I buy the Tier 3 pieces from the old Naxx? I've seen some people with the item set but I want the old set not the Wotlk piece set?

[Hogger]

You can only obtain them from the Coins store as far as I know.

[Disktrasa]

Since the old naxxramas was removed from game in WOTLK and ported to Dragonblight (northrend) it was revamped alltogether so the old Naxxramas gear became unobtainable for normal players.
The items still exist in the database thought and therefore you can pay coins to be able to get them.

On the side note there's several items that exists in the database but they are unobtainable in game for players, like Frostmourne (Lich kings weapon), Ashbringer (Tirion fordrings weapon) etc.