For maximum MK-9 Kit creation efficiency, you'll need a Scavenger, Cybertech, and then either Armstech, Armormech, or Synthweaving (with Synthweaving needing Archaeology as well).
Cybertech can craft the lowest material price MK-9 parts by crafting droid parts and RE'ing for the MK-9 parts (2 metal / 2 compound / 2 flux - will always get one metal back, sometimes get a compound back, rarely get a flux back).
Every other crafting skill, including Synthweaving, will require significantly more materials to craft items to RE for MK 9 parts.
What cybertech pattern gets you 2/2/2? I know you said droid parts but I can't seem to find it on my cybertech.