Knox is the best in the business. I've previously gotten PAX Twisted Fate, PAX Jax, PAX Sivir, and Riot Nasus.
Just picked up today from him: Silver Kayle, and Human Ryze
Here are the screens from all my purchases with Knox...
Soon I will be back on NA server, pm me if you want a referral, my username is the same as on this forum. I'm just a guy who enjoys playing the game and collecting rare skins.