This is a site that you may want to check.
http://pilot.familysearch.org/recordsearch/Marriage
Joseph Conlan, Dublin south, Oct-Dec. 1941
Vol. 2 Page 549
Annie Lynch, same information as above.
There is a death listed for Joseph in 1950. Do you have Joseph's death certificate. it may hold valuable information.
Also do you have any details about his siblings and parents. That may help you find his grave as well as Stanleys.
Hopefully, by using this site you can check all the Conlan's and alternate spellings to see if any names match what you know (your Mom and uncle) and also the Prenderville's. I didn't find any Stanley Conlan's or Prenderville listed but there are quite a few others listed. She may not have been born in the Dublin area. You did say that you had birth and baptismal certifcates for your Mom and uncle. do they list the church where the baptism took place. That is another starting point.
I assume that Annie Lynch Conlan is deceased. If so, do you know where she is buried and if it is in Dublin. I would start with the religious denomination and work backwards from there. The marriage certificate for Joseph and Annie should tell you where they married. If they married in a church and attended that church in Dublin, there is a good possiblity that Joseph is buried there.
Good luck with your search.
Val