UbiJustin has confirmed in this reddit post that the gold skins to support the pro league teams will be available September 12th. The purchase of these skins helps support the current Season 3 Pro League teams, so help your brothers out as they strive to provide entertainment for you while living on a modest ramen supply!
According to this blog post
These Gold sets will be available on Jäger, Fuze, Twitch and Thatcher. You will be able to pick up the Gold Dust Line Weapon skin, Gold Operator Chibi, and Gold Operator Headgear for $7.99 each. If you want to expand your options, you can purchase all four sets for $15.99.
I must admit, they look pretty snazzy!