The Willow Triplizer is available at :
Harris Cyclery in Boston
The TA Triplizer is available at
Harris Cyclery in Massachussetts
and includes all mounting hardware
It's also avilable at
Peter White Cycles in New Hampshire.
The Jim Merz Triplizer is out of production.
The Stronglight 135 bcd modern triplizer may require the inner spider of a Campagnolo Record / Chorus crankset to be ground away (I am not sure since I do not own one of these cranks.) This is not desirable. (Photo Courtesty of Andrew Muri of www.YellowJersey.org).