FM: Comstar has a picture of their Second Star League uniform, though it seems somewhat stylized given the description in the text. As for the stripe, I always imagined it on the front, going over the left nipple area and down the center of the left leg, with an additional one on the outside of the left arm. Remember that epaulettes and shoulder areas are a mosaic of glossy black in imitation of Nova Cat fur: I picture something like the a Western shirt's yoke, made of interlocking lozenge shapes, with the stripe terminating at said shapes: think of the bottom edge as \/\/\/ on one side and \/\//\\/, where the stripe goes straight down from the edges of the /\. This is really hard to describe without sketches or hand symbols.
I'd go with heat transfer vinyl for the shoulders and stripe. Oracal 651 is an inexpensive one. As a base, your first link looks spot-on to me, with just a bit of work to convert the collar into a mandarin one...a modification I personally have made to a boilersuit for a Fallout cosplay years back. And for the vineer pouch, I have a feeling some have hand-sewn sinew and leather medicine pouches, others full-on sporrans, and everything in-between.