It looks to me like 'Abraham Darby,' a fragrant rose introduced by David Austin. (Other names for this rose are "Country Darby' and 'Abraham.') Click on the link below for photos:

Here is a link that might be useful: 'Abraham Darby' photos

Thank you, Petaloid, but A. Darby does not seem to be exactly my rose, I was told about Alchymist which seems to be more like my flower...
I got very few guesses on various forums, A. Darby, Alchymist & Papy Delbard (most unlikely to be found in New Zealand, I believe!). So there is not much choice and Alchymist seems to be the winner!
Many thanks.