Have you tried the search facility at David Austin roses here:
http://www.davidaustinroses.com/english/Search .asp?Theme=
I've just bought a "Lady Hillingdon" which is pretty close to what you describe but it's more yellow than copper.
Check out the size that you want it to grow to. It's listed in the individual description of the roses
Crown Princess Margareta Clg might be good but it's only about 6-8ft or possibly Compassion 10ft.
Both of those are classed as apricot rather than Copper Gold. Bouquet d'or is more coppery
http://www.rosegathering.com/bouquet.html