Somebody else is starting a Duca D'Aosta mold project so I'll be building the Java and Trento plugs next.
Last evening I was looking at UK model boat websites and found a fully enclosed 3:1 reduction gear system for 380-400 motors that might be suitable to drive the center shaft of a Java Class CL. It's designed to mount on the end of a 1/4" shaft tube with a gear on the end of the prop shaft within the housing. The motor sits about an inch higher than the shaft so wouldn't be slowed down by water until flooding is severe. I've got a gear system of the same design for 500 series motors; used it for a while in HMS Courageous before replacing it with a belt driven reduction gear system.
Not only is the Algerie beautiful. But some sources say that it was one of the best Treaty cruisers in the world. No problem. We Frogs must stick together. Mikey