Why not Duchess of Albany? It has a flower form that is quite different than that of Etoile Violette, it blooms for a good portion of the summer for me also.

'Hagley Hybrid' (aka 'Pink Chiffon') would work well also. Mine is just coming into its primary bloom season and will continue through September/October. A beautiful shell pink color. It is planted to grow through a Clerodendron (harlequin glorybower) that blooms white but with persistant magenta calyxes and turquoise berries and the combination is pretty dramatic.

Funny, we are close geographically but my Hagley is done for the season already and started about six weeks ago.

Thanks for the suggestions. I might have to try and get my hands on both a Hagley and a Princess Di!