Puirt-à-beul are often named simply after the first few words in the lyrics, however I thought I'd heard this one before so did a bit of searching and found this set by Julie Fowlis:-

https://www.youtube.com/watch?v=2StWqayUvSE

The first song in the set is called " 'S Toigh Leam Fhin Buntata 's Im ", and appears to be the same (or very similar) tune, but different lyrics.