There are a few different ways one can approach this. One of them is to do a new class for each type. The new class for the confessor for instance would have limited magical powers of domination that would grow throughout the levels in strength and duration.
Another way to do this is through the use of a specific magical item that follows the character throughout their career. The seeker would have a magical sword which would grow with him in power as he grew in levels.
Remember in the world of the Seeker magic is special. The spells would be different and the items would be different. The magic would not be usable by just anybody except in potion form. In the game there would have to be some kind of magic sense, mundane, and pristine untouched feats that would allow the use or non-use of magic.
Another way I could do it is to use the existing classes as Ladyskunk has suggested and just modify them a little by changing out some talents. In such a situation I might use an aristocrat or perhaps a modified witch type and add the confessor's ability to dominate others and her ability to use two-weapon fighting in an almost rogue-like ability.
The last way to do this is through the use of specific feats and possibly new feats. I could also give both the seeker and confessor the dodge arrows, dodge and mobility feats fairly early as they demonstrated them in the shows multiple times.Since not all wizards can heal in the show I could decide to make a feat that allowed Wizards of the First Order to take the ability to do healing magics once they reached this peak of power.
The key with any of this is since Pathfinder is a level-based game you want to allow them to grow in power. You do not want to start off all-powerful. It is possible to give the confessor the ability to dominate others so many times per day from the get-go and perhaps give the seeker some magical attacking abilities but do not go right from the bat and give the Confessor the Blood Trance or the Seeker the Power of Oden.
Here is one take on a Confessor type using a rogue as a base
Abilities of a Confessor
Feats: unarmed attack, two weapon fighting, dodge, mobility, dodge arrows, spring attack
Talents: Sneak Attack (as per rogue)
Spell-Like Abilities: Dominate Person (touch) Duration: Indefinite (1st), Command (Confessed) (1st), Detect Thoughts (2nd), Suggestion (ranged) (3rd), True Seeing (6th), Dominate Person (range) (8th), Dominate Person (mass range) - Blood Trance Duration: Indefinite (10th)
As you can see my purpose was not to butcher or change your idea of what this story is or should be about but rather point to ways to be playable. If you would like I can expand on this and actually do more work into the specifics - perhaps work up an actual Seeker Class, Confessor Class, Mort Sith and Wizard class using the show as a guide? That is entirely up to you as I am going to base my decision to continue this thread with the responses I receive. If I do not receive many I will keep what I have designed to myself as I do not wish to offend anyone with my ideas of the Seeker campaign which may be different from your own.