slackware.uk mirror (Default)
https://slackware.uk/slackel/

Slackel mirror
If you want to sync the complete Slackel repository you can just use:
rsync -a --del slackware.org.uk::slackel slackel
That will create a "slackel" directory with everything in the slackel repository in it and you have to do nothing else. Just make sure that this command is run regularly, so your mirror is kept up to date.

sourceforge mirror
https://slackel.sourceforge.io/repo/
https://sourceforge.net/projects/slackel/files/repo/