Although this subject is well outside my expertise -- my interest stems from listening to sound recordings of Irish musicians singing in Gaelic, and I am not schooled in either words or music in this tradition -- I want to get this little quest underway and to specify what is missing and what I am looking for.

Let's begin with the melody, the music. Two fairly well-known melodies have lyrics referring to the following:
Eibhlín a Rúin
Aileen Aroon
Eileen Aroon

Only ONE of the two melodies interests me. So, let me describe the song that I wish to eliminate from this thread. The tune itself is linked to and referenced with "Robin Adair" and "Lady Keppel." Again: this is the one I DON'T want here. The reason I eliminate this version, is that Mudcat's Digital Tradition, along with several Mudcat threads, already document the melody, the Gaelic/Irish lyrics, and the English translations for this version. There is no need to duplicate, on this thread, what is already well represented at Mudcat.
I have yet to locate any file, be it printed sheet music or a MIDIfile, with the other melody for Eibhlín a Rúin, which is modal and highly ornamented as in sean-nós tradition. This is the song I am looking for.

Now, the words?
If you pull up DigiTrad files with "Duca tu non vanna tu, Tuca me sni anna me," you are a little closer to the lyric that is missing. I say it is missing because the sung lyrics in quotes here are actually Gaelic taken down by a listener who has no clue how to spell Gaelic. Now, I ask you: are you aware of a DigiTrad file at the Mudcat Cafe which contains
"Dtiocfaidh tu nó 'n bhfanfaidh tú, Tiocfaidh me 's ni fhanfaidh me" ?
because I have searched in vain for this lyric with this spelling in a DigiTrad file --
and there are SEVEN Eileen-Aroon/Aileen-Aroon DigiTrad files at Mudcat.

In conclusion, one of the oldest of traditional Irish songs needs a little more loving care and attention here, and I hope you all will come to this song's aid. Many thanks.