The GWR period
The Cambrian lines of the GWR are a popular choice among modellers, and there have been some excellent layouts depicting the post-grouping GWR days or the BR(W) period.
Modellers wishing to portray this post-1923 era can (given the right choice of location) draw on the various kits and RTR models available for the standard GWR stock that operated the line during these periods.
To find out what stock is appropriate for these periods, you could have a look at the fairly good range of books that are available about the Cambrian (see below).
The Pregrouping period
If you are interested in modelling the Cambrian Railways in their independent, pre-grouping period (or if you want to use some ex-Cambrian stock on a GWR layout) you'll need to rely on the rather limited range of kits and/or scratchbuilding.
Nevertheless, if you persevere the Cambrian in its independent years offers many rewards, including some rather good-looking liveries and stock as the following pages will show.
Cambrian Railways No. 19 built to 7mm scale, as running on the Barrowmore MRG's excellent layout "Johnstown Road" (see more on the following pages).
The "Dukedogs" have become almost iconic representatives of the Cambrian in GWR days. Here is a 7mm example, built by Ted Kanas from a Gladiator kit.
Another well-known GWR class on Cambrian lines were the Manors. This is the Bachmann OO version.