I need only one of each of the three sets in Western Skyrim and I have killed a delve boss twice and got a set piece I already have both times.
It may depend on which piece you need. If you only need weapons for instance, those aren't on the delve boss loot table so it can't curate those items. They would drop from world bosses and public dungeon bosses.
i have my main house (grand topal hideaway) listed in the housing tours, it has multiple target dummies, scribing altar, and grandmaster stations (in progress being filled out), as well as almost every antiquity furnishing on display to preview them