In order to access the Blood Ruby Mission, you will need to first complete the mission: A Cultural Exchange
Once completed, look for the star icon on the map.
Yak Farm Mission
In order to access the Yak Farm Mission, you will need to complete the mission: A Key to the North
.700 Nitro Elephant Gun, Sandman 1911 Pistol, Driller PKM
As soon as you have the ability to purchase weapons, these weapons will be available for purchase from any shop and can be equipped immediately.
In order to access the Butcher’s Machete weapon, you can equip it as soon as you finish the mission: The Mouth of Madness.