Following https://docs.hortonworks.com/HDPDocuments/HDP2/HDP-2.6.1/bk_command-line-installation/content/downlo... I could not find hdp_manual_install_rpm_helper_files-184.108.40.206.129.tar.gz.
wget http://public-repo-1.hortonworks.com/HDP/tools/220.127.116.11/hdp_manual_install_rpm_helper_files-18.104.22.168.1... fails with 2017-08-25 02:05:45 ERROR 404: Not Found.
Latest version I could find is http://public-repo-1.hortonworks.com/HDP/tools/22.214.171.124/hdp_manual_install_rpm_helper_files-126.96.36.199.8....
Can I use that one for 188.8.131.52 as well?
I think you can safely use it as a reference. That's a minor release between 2.60.3 and 184.108.40.206 just simple bug fixes and errata so I would say YES .