Suggest you go to www.irishgenealogy.ie which has some Dublin church records. I located the 1848 marriage which you already have. I also located the June 23rd 1847 baptismal record for his son Francis at St. George's church. The surname was shown as Hare. The mothers name was shown as Jane Hare. Unfortunate that her maiden name was not shown but at least you know that her first name was Jane.
Civil registration of Protestant marriages started in 1845 and I was not able to find an index record for the marriage which leads me to conclude they were married before 1845.