Brooks made, for the Cannondale 2000 series touring bikes in '03(?), gray Professional series saddles. I've heard of B17's in gray as well. Did they ever make olive green ones? I'm dying to own one of these oddities.
Well they still make a green one. Not quite "olive" though:
I've seen pictures of the gray Brooks you mention but I don't remember if there was a B17 version.
there was a single gray Professional at yellowjersey for quite a while. my room mate owns it now. I have never seen another one before or since, which is too bad as I rather like them.
There was a NOS gray Team Pro on Seattle's craigslist a week or so ago for $75. I pointed a friend to it and he said it went in a bidding war ...