I would like to suggest that Hornby’s next era 1 locomotive should be Matthew Murray’s Salamanca. Built in 1812 (17 years before Stephenson’s Rocket), the Salamanca was named after Wellington’s victory at the Battle of Salamanca. It appears in a watercolour by George Walker (1781–1856), the first painting of a steam locomotive. A model of the locomotive, built by Murray in 1811, is part of the collection held at Leeds Industrial Museum. It is the world's oldest model locomotive. See https://westleedsdispatch.com/worlds-oldest-model-locomotive-is-on-track-in-armley-museum/ for a picture.