Hello! how interesting ... a transcription is just copying exactly what's on the stone, just names and dates.After reading what you wrote, they are now more than just names and dates!I'm not related, but many of my ancestors are buried in St. Francis.
If you live locally, you can stop in at the cemetery office, and they could give you the exact section and gravestone number(I guess it wasn't carved into the stone, which is why I made ????). From the diocese office you can request "Order of Internment" paperwork for the grave, a form is filled out for each time the grave is opened, with name, address, age, undertaker, etc., etc. - and hopefully info like parents' names. Anyone can request this, I believe ... I've done if for several graves over the years.
Death records can also be found in the index of State wide deaths at the R.I. Archives (from 1853 to 1955) - the cost is only 0.15 per page. The RI Health Department charges (I think) $15 for an offical copy. Since Gavin is kind of unusual, probably any Gavins you would find might be related somehow. I did this with my DENNENY ancestors - very rare name.
There are more transcriptions of Irish names/graves at the "SNE Irish" web site, done by other volunteers and myself, from many cemeteries all over Southern New England.