Beau Rivage is owned by MGM-Mirage. If you have a MGM Players Club card it'll work at the Beau or any of their other properties (MGM Grand, Bellagio, Mirage, Treasure Island, etc). I dont think the bennies are transferrable though.
If you dont have one, grab it online and see if you can use it immediately to get the discount.
http://www.playersclub.com
If that doesn't work, get a credit application, apply for a line of $100K or so and then ask again.