Also be aware, for lower level, the Skullduggery Cap from Final Enemy in Saltmarsh gives 3 uses of Death Ward at ML3, 10 min duration each, which will provide Deathblock plus other buffs
Deathblock items are pretty common, especially as you level up, so its of arguable value to spend the 95 Store points for an augment. Definitely not worth it to socket in a Nightforge Gorget - much better to just buy a 100% Fort sapphire (for 12 AS or 20 Tokens, ML8) and socket that in a Deathblock item