By "package source" chocolateyChocolatey means the location of the *.nupkg file. But it is stored in the chocolatey.org site and nowhere else. The package itself dodoes not provide an option to change the location of the distrodistribution itself. Manual
Manual download/installation is the only solution.
Update
Since build 15.07.01 the download location for chocochoco
moved to githubGitHub.