I can't help with the type of fabric I'm afraid, but I really do advise making a reverse Kingussie style of pleating as I have had to unstrap a kilt and then work it out of the grip of the bushes when wearing a conventionally pleated kilt - I gave up on them after the second time.
Reverse Kingussie has an inverted pleat centre back, I make it double the size of the small pleats, and the small pleats then are mirror imaged, and they point backwards like the feathers on a bird's wing.

I make two deep pleats beneath the aprons, and that means no problems climbing steps or gates or walls. The aprons on mine are slightly narrower than on a traditional kilt, so there might be 24 or 26 small pleats.
I'll just look up Supplex and get back to you if it looks a likely material to try.

Anne the Pleater