Where can I find a robe like this?

Hopefully someone will be able to help me even though I know it's a long shot. On the tv series "Still Standing", Judy Miller (Jami Gertz) wears a long gray robe occasionally. I'm not sure which episodes, but I've seen it a few times and I CANNOT find a long gray cotton woman's robe anywhere! The one that is on that show is the look I'm going for. So if someone could point me to a website or store I'd be very grateful. Thank you!