Cabra road and Collins barracks

I am tracing my partner’s family tree. His surname is Harvey. His father was a soldier in Collins Barracks and his Mother Annie Conroy is listed on the marriage certificate (15/8/1953) as a spinster living in what I think says Cabra Road Dublin. He  never knew his parents. I am able to go back a fair way on his father’s side but it is his mother’s history he is particularly interested in and I am getting nowhere. I have the marriage certificate but cannot find a birth certificate for her and consequently a death certificate. I’m at a loss. How do I go on? Where do I look?