The Wiser's 18yr old is wonderfull rye, best Cdn. rye i've tasted. It is readily available at LCBO, but that doesn't help much for those looking south of the boarder. I'm sure it's marketed in the U.S.A.
Have you tried an online liquor broker?
I too love Wiser's Very old. I was living in Jacksonville Fl. for 10 years and the owner of the place where I purchased my Crown Royal steered me onto Wiser's. No comparison, both better and cheaper (IMHO). Try the above site. I sent an email to the contact place and actually got an answer. I need to make a pilgrimage to Georgia to get a couple three bottles.
I've read the Corby Distillers page listing the states in which Wiser's is available, and it's not entirely accurate. As I wrote earlier, I purchased both the 10 and 18 year expressions in Kentucky even though the state doesn't appear on the list.