Portland Cyclewear has some options. I just happened to see their link here on the bikeforums a few minutes before viewing your post. So I have no personal experience with the company or their products.
Wool, $39.00:
http://www.portlandcyclewear.com/cat...57/5120808.htm
They also have 3/4-length "messenger" pants that are $72.00 -- or $39.90 if you buy a dozen or more: know 11 same-size friends who cycle?
http://www.portlandcyclewear.com/cat...57/5102958.htm