For what it's worth, "bicycling" thermal under pants are cheaper than "motorcycle" thermal under pants and are exactly the same thing.
www.nashbar.com
They are wind blockers and thermal lined on the inside with something like hipora and fleece. I don't really know what all that stuff is, but it works.
Same with a Balaklava. In any temps under 40, I wear one. They're just good to have.
And, some people have a higher tolerance to cold than others. I am a cold weenie, but I wear lots of warm things and I am able to ride through the winter.