Buy from the Artifact Collector for 23 Planar Nuts
You will find the Artifact Collector in..
Tempest Bay – /setwaypoint 12976 11524
Meridian – /setwaypoint 6080 5135
Sanctum – /setwaypoint 7469 3004
You will receive a Planar Nut every time you hand in an Unstable Artifact set.
Planar Nuts are items in your bags, they will not be added to your currency tab, you will need to be very careful not to accidentally destroy them.
There are 23 zones with Unstable Artifacts, each zone has 6 Unstable sets giving you one Planar Nut each. A total of 138 Planar Nuts which is the exact amount required to buy all 6 squirrels.
If you complete all the sets and find yourself short of Planar Nuts then you will need to make a ticket to ask for the ones you miss.