Satchel Of Sinister exalted armour
In all previous cases, satchels for the stat combinations requiring recipe unlocks also required recipe unlocks. Acquired the same way as the armor piece recipes. Since sinister armor is not discoverable, the recipe for the satchel cannot be made the usual way. Unfortunately Anet seem to have forgotten about adding those recipes to drops (most likely due to the new “select piece” format).
So no, they cannot be acquired in any way currently.
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