Hi I am in WA too. Most roses need several hrs of sun but I have Rosa Nutkana that is mostly in shade and thrives. I don't know of any Floribunda or Hybrid Tea that will do well in total shade but you might try any of the rugosas or hybrid rugosa. Does this area get any sun? I have a Hybrid Tea,  Pink Peace that only gets morning sun and does very well.  Good Luck

Angel Face is a floribunda that is supposed to be shade tolerant.
Chrysler Imperial, Blue Moon, Blue Girl, Swarthmore, Garden Party, and Bourbon are all shade tolerant hybrids.

I've found that many roses tolerate part-shade in Perth - they may be a little leggier but some roses definitely appreciate a bit of shade in the hot months. Success depends on 'how much' shade and whether the shade also comes with aggressive hungry and thirsty tree roots.
There are so many varieties to choose from and everyone has their favourites - it's a very personal decision.
Melvilles Rose Nursery in Carmel have a wonderful display garden and knowledgeable staff.
Swiss Rose Nursery and Roworths also. It's worth visiting and seeing how the established plants look in a garden setting.
'Sunlit' is an excellent rose that tolerates a semi-shaded position well. It's one of Alister Clark's Australian bred roses, blooms 12 months of the year in Perth, has beautiful healthy evergreen foliage and hardly any prickles. The bloom colour is an apricot blend. You should be able to get this from Melvilles - if not immediately, then in October.
If you have the space, you may be interested in Tea or China roses which are pretty bullet-proof in Perth and many of them grow happily in a semi-shaded position. I know it's a deviation from your request for HTs and floribundas, but Mlle Cecile Brunner, Perle d'Or and Mme Jules Thibaud are sensational smaller roses - healthy, tough, beautiful and so floriferous in our climate.