It'll lower your overall dps, but dispersion is nice in some cases (when soloing triple ups, absorbing a 5k hit might mean the difference between winning and losing a fight).
Once you hit level 70+, there's a few easy pieces to get:
Forest Giant Trinket: aITEM 112355444 1065117516:Forest Giant Trinket/a - Quested Reward from Kylong Plains
Runed Bracers of Diffusion: aITEM -1531609317 173257584:Runed Bracers of Diffusion/a - Drops in Kylong Castle (It's tradeable, so check the broker)
Sash of the Nathsar Tribe: aITEM 969616858 1816624503:Sash of the Nathsar Tribe/a - Drops from mobs in Fens (It's tradeable, so check the broker)
Embroidered Sebilite Mantle: aITEM 1506225763 606552788:Embroidered Sebilite Mantle/a - Purchased from merchant in Outer Sebilis. This one is a PITA since you need 30k or 40k faction with Outer Sebilis.
There's others of course, but these should be fairly easy to acquire (aside from the last one).