The L4 is a project that has interested me a number of times, the options are:
keep an eye on Barnstormers.com in the warbirds or antique/classic areas under Piper or projects
join the cub club http://www.cubclub.org/ they have classified ads for members
or build a new one via Cuby plans from wag-aero http://www.wagaero.com/
regards
Mark Pilkington