There are many other minor dignitaries in Star Wars: The Old Republic that appear only briefly and do not wear easily generalizable costumes. However, costumers are welcome to seek Rebel Legion and Galactic Senate Detachment membership with any costumes of good or neutral-aligned dignities with sufficient front-and-back and head-to-toe references. Screenshots from in-game as well as 3D turn-arounds from Jedipedia make excellent resources.
Below are snapshots from Jedipedia and elsewhere of various SWTOR dignitaries. Interested costumers are encouraged to do further research on these costumes if they would like to assemble any of them for membership.