Python's distutils does not have any support for uninstalling, however running the commands below should uninstall most of NautilusSVN.

find /usr/share/locale -iname "NautilusSvn.mo" | xargs rm 
find /usr/share/icons/hicolor -iname "nautilussvn" | xargs rm 
rm -rf /usr/share/nautilussvn 
rm -rf /usr/share/doc/nautilussvn 
rm -rf /usr/lib/python2.5/site-packages/nautilussvn*
rm /usr/lib/nautilus/extensions-2.0/python/NautilusSvn.py