are they sold in pairs

Sure thing, the one product comes with two racks. Just be aware, the locking mechanism on this rack is cool and all, but won't keep your skis safe. The rack's crossbar attachments can be undone even if locked, which means that not only can your skis get swiped, but your racks too. Maybe I'm more paranoid about this because my racks fully loaded with skis is worth more than my Subaru, but I thought it was a gross product design oversight.

If this kind of thing bugs you, get the Yakima PowderHound or similar racks. You'll be happier with them anyway, they just work better (like opening/closing in cold environments).

Check it:
http://www.backcountry.com/store/YAK0220/Yakima-Big-PowderHound-Snow-Roof-Rack.html

and don't forget the lock cores…
http://www.backcountry.com/store/YAK0017/Yakima-SKS-Lock-Cores-2-pack.html

Slightly more expensive, but worth every last blood-stained penny.
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