But if you want to get it quik, do this:
*ENORMOUS SPOILER!! BEWARE!!*
1.Finish the Ithorian missions Telos, and obtain the Lightsaber part.
2. Go to Nar Shaddaa, go into the Flophouse (at the docks) use stealth on the most left 'house', and you;ll see a cutscene where 2 crooks are planning a robbery on Voga.
3. Go to the Entertainment section, and make your way into the bar. Again, use stealth to hear the plan of the 2 crooks on the right. Then buy Juma Juice at the barkeeper.
4. In the cantina is a guy dancing. Talk to him, and say handmaiden/Visas/yourself will do it.
5. Dance at Voga, and he will fall asleep. Then pour some Juma Juice into the little bowls in the corner. You'll see a cutscene of the 2 beasts falling asleep as well.
6. open the door near Voga, and grab the Second saber part and some other stuff.
7. Visas is now triggered, so visit your ship, defeat Visas, and obtain your last part.
It's (it think) the quikest way to obtain it, without doing enormous main quests. And remember: You can have HK-47 after Nar Shaddaa...
Hope it helped ^^
"I think the Devil ****s Dutchmen."