I do think with something like a bespoke training layout, funding it is maybe the easy bit. Getting it stored, transported, and having somebody who will look after it and make sure it turns up in working order ready to use are probably harder things to crack!
It does strike me, looking at the requirements:
http://www.nmra.org/dispatcher (which TBH aren't *that* exacting for this one!) that we've already built and we already run (at increasingly regular events which are accessible) modular layouts providing the majority of the roles listed, and that could accommodate the others if we'd decided to make it so
* - and I know that there are modules in existence already that could provide a great basis for doing so (or going further with training sessions allowing folk to try out TT&TO or whatever) again.
I think the challenge from that approach is getting the owners of the right modules on board to supply them for a given event...
(
*I think one key here is if folk want to be doing something specific towards this,
tell the organiser...)