For mainly caucasian girls, CocoCollective or TempGF are good agencies. Priced 300 to 400 per hour.
For more expensive, dollhouse and VME. 450 to 500 per hour.
For mix of caucasians and asians, AsianFever or 1122 group.
For all asians there is lots but Xiao Dimsum, icon604, korean604, private...