If some items or rather item bases are rare that doesn't mean they can't drop at all. Moreover you can farm
Henchmen Trophies
Henchmen Trophies
(Legendary Set)
Bilefroth Skin
Blackskull's Horns
Doomcloud Spine
Stareye's Claws
Fangskin Scales
Set Bonus with 2 or more set items:
+2 to All Skills
15% to All Attributes
Set Bonus with 3 or more set items:
-25% to Enemy Elemental Resistances
Elemental Resists +25%
Set Bonus with 4 or more set items:
5% Deadly Strike
Physical Resist 10%
Set Bonus with complete set:
1% Base Block Chance
50% Movement Speed
+35% to Spell Damage
+1500 Defense
Elemental Resists +30%
+150 Life after each Kill
set parts from K3K nowadays and it was impossible in the previous MXL version. You'd have a much better chance to get those rare items at Duncraig because of the sacred item drop basis though.