Where in the Alderaan Mountains is a MGGS?

Space Travel to Alderaan

Taxi Travel from the spaceport to Outpost Talarn

Follow the trail yellow brick path to the northwest then loop around to the south

Follow the Woodland Path

Lain-Ricie is the vendor in a small clearing at coordinates 1866, 1090

The MGGS is 10,000 credits and is unique.  It is not BOP.  You need it in your inventory for the +10 datacron event.

The description on the MGGS is:
The Magnetically Guided Grappling System or MGGS is standard Magball equipment.  Magball is a competitive sport where opposing teams fight for control of a magnetised ball which can be scored in the opposing teams goal.  The MGGS can also be used to move the player around the arena by targeting the various magnetic points that are setup.