Steamunlocked F1 2013 Link
While F1 2013 is (no longer sold or supported by the publisher, EA/Codemasters), it is still copyrighted property. Downloading it from SteamUnlocked is digital piracy. Even though you cannot buy it, the rights to the game belong to EA. You are not at high risk of a lawsuit for downloading a decade-old game, but your Internet Service Provider (ISP) may throttle or flag your connection.