You can get that from technet if you have an account over there Subscriber Downloads | Search and download thousands of Microsoft products and get Product Keys
Or you can use RT Se7en Lite to slipstream SP1
RT Seven Lite - Downloads
---------- Post added at 01:56 PM ---------- Previous post was at 01:53 PM ----------
MS has released it, Can be found under Operating systems >> Windows 7 Subscriber Downloads | Search and download thousands of Microsoft products and get Product Keys