You can't ever guarantee that the name will be unique: I know several children of seven of the names posted above (Fergus, Dexter, Matthew and Emma being the most frequently encountered).
So the first thing OP might like to do is steel herself for the possibility that sod's law means that whatever name she chooses, there will be another one in the same street.
But if you mean simply less frequent, rather than trying to be unique, then there how about:
Andrew, Peter, Stephen, Edmond, Neil, Edwin, Rupert, Dominic, Graeme, Hamilton, Jeremy, Lemuel, Viktor, Desmond?
Bryony, Maura, Jean, Margaux, Jennifer, Miriam, Penelope, Hilary, Ruth, Stephanie, Gladys, Edwina, Flavia, Joanna, Lisette, Yvonne?