Well one of the first questions you might want to answer is how good are you at folding a hakama? Cotton hakama tend to lose their pleats more easily than polyester, so I would get one only if you really know how to take care of it (or have someone willing to coach you). Polyester is much more forgiving (especially if the pleats are sewn in a la Bujin), especially in the heavier weight. Of course, if you ball it up enough they will still go away. (I still shudder at the memory of folding a 20 year old rayon hakama that had not been taken care of for an instructor at a recent seminar. He told me afterward that no one had even tried in the past 10 years - after
I had wrestled with it for 20 minutes!)
The second question is what color are the mats you routinely practice upon? Indigo dyed cotton can leave blue marks on the mats, which could be rather embarrassing if you practice on white canvas. Black cotton and polyester don't bleed as badly, if at all.
As for ordering, both Yamato and Iwata have direct order sites online.
Yamato - http://www.yamatobudogu.com/Custom_T...kama_s/154.htm
Iwata - http://www.alpha-net.ne.jp/users2/iwataco/frame2e.html
The Yamato site seems a lot more user friendly, has a more normal payment method, and offers more customization. Iwata is a little tougher to understand because the translation leaves a lot to be desired at times. They also require you to either email or fax them your credit card number (eek) or do a bank transfer. I would try calling Kiyota to see if they will ship to Israel if you really want an Iwata unless you are fluent in Japanese, but that's just me.
Let us know what you pick!