Check if there's an American Women's Association/Club (
www.fawco.org) where you are. If you contact the local group (they are independent, not chapters), you will likely find women who can help you out. In my AWA group, I discovered members of 5 or 6 sororities, and that was without a whole lot of effort. You may even find women who will be willing to help you prepare for rush. To say this is a charitable group is an understatement, so don't be afraid to ask for help. If you don't find answers, let me know and I'll see what I can do. I have a few other suggestions that I won't post publicly, so send me a PM if you want more help.
And in lieu of that you can contact the alumnae panhellenic in your "home" city. I know as a 3rd culture kid, you may not feel like LA is your home, but there is a big group there, and I'm sure they can help you get recs.