I for one would like to see your pattern for those bags made out of old gi. Sorry I've no suggestions for the old hakama.
I dont have a pattern, but go here for my inspiration.
Go to the tote bag link at the bottom of the left frame to see the bags. I think they're cool and almost self explanatory. Not only that, Iwata makes rocking excellent hakamas. And then, there's the joy of reading so much Engrish in one place.