This comes up a lot here at Shockspital: a Lefty Max comes in for service that still has the old Manitou damper in it. These are cool forks because they use the same chassis as other Leftys, but the damper is where the air spring would otherwise be and there's a big coil spring in the top half of the fork. The damper is also a lot simpler than a DLR/PBR/XLR Lefty, relying on a single shaft seal to keep the oil where it's supposed to be.
But, you guessed it--Cannondale doesn't make parts for these anymore. So if the damper shaft gets damaged, the fork becomes a very good candidate for a damper upgrade, including the new air spring system that modern Leftys use. This upgrade has a ton of benefits, not the least of which is the weight savings!
At top in the above photo is the stock coil spring from a 2004-2005 Lefty Max SPV/TPC. At bottom is the RockShox-produced Solo Air spring assembly which replaces it as part of a PBR/XLR damper upgrade on this fork. The coil weighs in at 256g. The air spring assembly is 39g (including the packaging!).
Weight weenies, rejoice!