git svn clone of a single directory of SVN repository
You don't want the standard layout, you want something like this:
git svn clone svn+ssh://path/to/repo/ --trunk=trunk/directory --branches=branches/*/directory --tags=tags/*/directory
Prepare and enter the local project directory:
mkdir local/project/path
cd local/project/path
Initialize the local git repository with svn remote and fetch the data:
git svn init http://my_svn_server.com/repository/project/location
git svn fetch
Credit goes to Gabriel Saldaña: http://blog.gabrielsaldana.org/using-git-with-subversion-repository-subdirectory/