Get recruit gear, do Ilum/BH dailies, run HM flashpoints (don't forget to pick up daily/weekly quest on fleet), EV 'AND' KP via group finder (yes you can do GF ops twice a week, twice the reward) which is doable even in recruit, but if you run a couple HM's you'll be half in columi already, by then you'll have some daily comms too which can buy a rakata implant already, you'll have enough BH comms for an earpiece/waist/wrist, and a mainhand you can buy from the Tionese guy and upgrade the mods when you get better ones.

using this strategy i was full Columi+ in a weekend on my latest 50.