Girls twin tips are no different than guys skis, other than they are typically softer and/or narrower + shorter.
Some anatomically correct carving or race skis will put the binding closer to the center of the ski than on mens skis to compensate for weight distribution in a typically shorter female body, but with twin tips, you're mounting in the middle of the ski, or at least close to it, so this doesnt trancend different ski types.
To answer the main question though, Boys skis are quite fine for girls, and I happen to know quite a few girls who own and use skis that were originally meant for males.
As for girls skis that are over 95, but under 167..
-K2 makes the Missbehaved for next season.. its basically this years Seth, but I believe they are making it down to 157? Not sure if its still 98 underfoot at that size... but worth checking into. Take into consideration that there is rocker in the ski.
-VOLKL makes the Kiku for 09.. which is a Gotama in womens sizes and with womens graphics. I believe they are making them in size 160 and 167. It is 105 underfoot in all sizes.
-MOMENT makes the Sierra, which... not sure if they are making it smaller than 170, but I understand its based on the 96 underfoot Tahoe. They also make the Pika, which from my understanding - based on the Ruby. Not sure if thats any smaller than 170 either...
-LINE has the pandora, which is 139-110-137 and based on the Elizebeth. Not sure if its smaller than its twin brother which is 172, but look into it when it comes out next season.
Other than that, I cant really recall any other womens skis over 95. Everyother womens ski i can remember is at or around the 90 width...
Good luck hunting.