Thanks yet again Liz and Frances.

Frances,
You were right! I have managed to find this very verse among the hymns on Manx Notebook. The full, correct transcription is:

Dooisht liorish feiyr y chayrn,
Nee’m girree seose veih’n oaye;
Nee’n briw cheet, lest gloyr soilshean,
Bee’n aer myr coirrey lheie:

It's verse 4 of Hymn 20 [And am I born to die?].

The third line on the photo of the stone is mostly obscured but from what I can read this corresponds exactly to the above. The fourth line will almost certainly be there but still hidden by the moss.

I noted that some of the hymns on Manx Notebook have English translations alongside, but not this one. Can anyone help with a translation now that I have the full verse.

Liz,
Please do not go to any trouble on my account, you have already done so much. I think I now know what the inscription on the stone says in full. Many thanks again for finding this for me!

Patrick