I'm gathering some old ISOs of Ubuntu MATE to preserve a bit of history, but I can't seem to acquire a copy of the amd64 build of the very first 14.10 release!
14.04 actually was the second release while Ubuntu MATE was an unofficial "remix"
Luckily, I managed to salvage 45.3% from an archived amd64 link on the Internet Archive, but it's missing the remaining 54.7%.
If you've still got a copy, please consider adding it to your Bittorrent client and seed it to spread the retro-re-retrospective past.
Thank you to the mysterious torrent user who seeded 14.10 i386! This has been archived at https://releases.ubuntu-mate.org/archived/utopic/i386/