For consideration: "Lifelock Bindings"

Wondrous Item, (adventuring gear) Rare

Glittering in the light, these bindings are magically infused with diamond dust, giving them remarkable and near infinite healing power.

As an Action, these Bindings can be used on a creature that has been reduced to 0 HP to stave off death (as a Healer's Kit) any number of without expending the item's potency. The creature becomes Stabilized, no long needing to make Death Saves.

Alternatively, if a creature has passed beyond the boundaries of healing and into the realm death, the bearer can use an Action to cast the Revivify spell, using the Bindings as the material component. The Bindings then become normal, nonmagical bandages.

"Not... yet..."