Actually, Dunlop (now a bastard child of Goodyear) has come out with a Grantrek SJ5 winter tire in the exact size for the MO -- 235/65R18. Dunlop doesn't even list it in their product info on their website, but a few Nissan dealers can get them in. I think some of the Canadians on this site have had them installed around the Ottawa and Montreal areas and have so far been pleased. I think the cost was around $160 per tire.
Also, Nokian makes the Hakka SUV winter tire in a size that's VERY close to the MO's size. It's 235/60R18. This makes the difference about 3.1%, resulting in a speedo difference of 3.7 km/h at 120 km/h (that is, when your speedo says you're doing 120, you're really only 116.3 -- big deal). The reviews and testimonials I've read on Nokians say they're nothing short of spectacular. Unfortunately, they're not widely available like Michelins, BStones, GYears, etc etc but they are available. There are a couple of retailers in Ottawa, though I found an excellent customizing shop here in town that can get them SIGNIFICANTLY cheaper ($265 per tire) than the quotes I received from Ottawa (about $60 cheaper per tire). Also, Nokian's level of production isn't like Goodyear's, so they frequently run out of stock on certain tires, given their increasing popularity.
Barring any new developments from the other manufacturers, and given my overwhelming level of disdain for Goodyear/Dunlop, I'll be ordering a set of the Nokians this coming summer/fall for next winter.
For info, the website below is an excellent, small independant site devoted to testing winter tires. It's a small operation so the scope is often limited but the info is excellent and unbiased. Hopefully, they'll have the latest test results up soon.
www.snowtire.info