Bike's not
that old. (Pity.) Plus, it's a little late in the season for the waxed cotton, no? I'm thinking middleweight tweeds or cotton twill.
Barbour's "
Brewster Breeks."
Also available in stretch black moleskin. Rawr.

For super traditional outdoor wear, it's hard to beat Barbour. Me, I keep my eyes peeled for cheap knockoffs. Unfortunately, no one bothers w/the more eccentric stuff that could possibly be used for cycling.