Hi,
Sorry for the late reply - I haven't been on DA in *ages*!
I custom dyed all the fabric except the orange-ish color that was used for the tunic borders & designs and the yellow for the belt and boot cover lines.
My base fabric for everything was a linen/rayon blend from Dharma Trading. It's very nice with good drape while breathing well for summer costume wear. It does wrinkle a lot, however, and you have to be sure to finish all interior seams to avoid excessive fraying. I used the Dharma Fiber Reactive Procion Dyes and followed their instructions on the website. It's a little messy and requires careful attention to proportions amongst all the required ingredients, but it's not particularly difficult. I found a spreadsheet useful in calculating the quantities for each color (I was doing the fabric for a 4-person Avatar group).
The darkest color is a black, #44 Better Black. It requires more dye and salt than usual plus a special fixative, but all the info is available on the website, as are all the supplies except non-iodized salt (I cleaned out my grocery store of the stuff multiple times with this project!). The medium red that is the bulk of the undertunic and pants was #10 Fire Red, while the darker red of the arm bands was #136 Oxblood Red.
Hope this helps - let me know if you have any other questions.