Is there anything else on RVR's site that you can suggest, that is hardy to 5b? 6a could work as well, I'm right on the zone border.

One of the reasons you may not have gotten many responses is that there aren't many grey roses that will survive in zone 5, much less thrive. I planted Aschermittwoch last year and it's showing no signs of life even though protected pretty well. I've grown (and killed) Grey Pearl, Lavender Pinocchio, Lila Vidri, Silver Cloud, and any number of "grey" looking roses. Haven't bothered to try Sterling Silver, as it's the wimpiest of the bunch in our zone. In general the weird colors - grey, russet, lavender - tend to be weak roses.

The closest to grey I can find on RV's website that is reliably hardy for me in zone 5 is Lagerfeld. It survived even the polar vortex reasonably well, and it's a light lavender with creamy-greyish tones. Pam's Choice by Barden is a hauntingly beautiful rose that I've tried once, and I think it'll need a protected spot in my yard. Ditto for Vol de Nuit that I'll give one more try.

Among the russets, I have been able to get Tantarra to survive with some definite babying, in my zone 6 pocket, but it's not robust by any means. Spiced Coffee, however, has been an absolute trooper and it reblooms pretty steadily in my zone 4 pocket. RV has this one in stock, and I recommend it.

Hope this helps!

Cynthia