Elepar has a long history of research and development pertaining to ScalPL oriented tools. Our primary toolset, L23 (pronounced "ell two three") has four primary components: A frontend for entering, editing, and saving (in textual SPLAT format) graphical ScalPL diagrams; a backend for constructing code automatically from those diagrams, for use in sequential, parallel (e.g. multicore) and distributed environments; a Director (as discussed in the book); and an optional annotation stage for providing additional guidance to the Director.
Although the diagrams for the "Scalable Planning" book were indeed constructed using the L23 frontend, final development and hardening for the retail market took a lower priority while writing the book. If a product like L23 might be useful for you, you can help its delivery to the market by registering your interest on our contact page -- e.g. by signing up for the L23 mailing list.