Joined: Jan 2009
Posts: 44,167
Likes: 6,390
From: New York, NY, and High Falls, NY, USA
Bikes: 1962 Rudge Sports, 1971 Raleigh Super Course, 1971 Raleigh Pro Track, 1974 Raleigh International, 1975 Viscount Fixie, 1982 McLean, 1996 Lemond (Ti), 2002 Burley Zydeco tandem
Oops, never mind. That's not 20.5mm at all!
It seems your only option is the Wald. Do you have a seatpost currently and are you looking to replace it? Or do you need one because your bike doesn't have one?