Good ol' google:
Alstromeria, Amaranthus, Hippeastrum,Antherium, Asiatic Lillies, Asters, Bamboo, Banksia, Copper Beech, Green Beech, Beehive Ginger, Bird of Paradise, Bouvardia, Calla Lillies, Celosia, Chinese Lantern, Christmas Lillies, Chrysanthenum, Clethra, Cornflower, Cosmos, Cows Udders, Crab Claws, Dahlia, Daisy, Delphinium, Dodda Vine, Easter Daisy, Figs, Frangipani, Freesias, Roses, Gardenia, Gerberas, Ginger Flowers, Gladioli, Gloriosa Lillies, Heliconia, Hyacinths, Hydrangea, Hypericum Berry, Iris, Molluca Balm, Larkspur, Lavender, Magnolia Foilage, Asiatic Lillies, Oriental Lillies, Lissianthus, Lotus Pods, Nerines, Phaelonopsis Orchids, Singapore Orchids, Protea, Queen Fabioli, Roses, Scabiosa, Snapdragons, Stephanotis, Tuberose, Tulips
You've got roses, tuberoses and lissies on that list so I reckon your David Austins would be fine.
My favourites on that list are Calla's (I'm having too), I think banksia looks great if done well, gardenias and magnolias and the orchids. But reading through that some of it's a bit climate dependent so it's best to chat to a good local florist - or do what I did and chat to about 7 and choose the advice of the most sensible!!
I know a lot of girls have the silk/latex but I'm not a fan. I don't like fake - if you don't want flowers don't have flowers, have something else. Each to their own though.