5 inch gauge wagon kit of parts

A set of parts to build a 5 inch wagon comprising machined components and castings, although with no chassis rails.

Obviously commercially produced - and to rather a nice standard, with CNC turned steel wheels, pre-formed leaf springs and Oilite bushes for the axles - but we're not quite sure by whom. No doubt one of the usual suspects will claim responsibility and let us know from whose drawing board they originated.