Do in Terminal (requires XCode with Command line tools installed):
curl -O http://rsync.samba.org/ftp/rsync/src/rsync-3.0.8.tar.gz
tar -xzvf rsync-3.0.8.tar.gz
rm rsync-3.0.8.tar.gz
curl -O http://rsync.samba.org/ftp/rsync/src/rsync-patches-3.0.8.tar.gz
tar -xzvf rsync-patches-3.0.8.tar.gz
rm rsync-patches-3.0.8.tar.gz
cd rsync-3.0.8
patch -p1