Hi Paul - you have almost the right spelling; enough so that i could find it in the special daylily database by just entering "cu" in the search field:
Daylily (Hemerocallis 'Cuivre River')
Very beautiful daylily - hope you'll upload one of those pics to the database entry (easy to do, just scroll all the way down and look for a hot-link to upload)
btw, that purple DL in your profile is also a stunner ... what is it?
The main daylily database here is at:
The Daylilies Database
hope this helps!