How to get Steflos Prime Stock in Warframe?

Steflos Prime Stock is an item dropped from Void relics.
You can find the list of relics below, and click on the links to see how to get them.

Relics dropping Steflos Prime Stock

Other items:
Steflos Prime Barrel - Steflos Prime Receiver - Steflos Prime Blueprint
Steflos Blueprint - Steflos Stock - Steflos Barrel