We need more info. What has 2-6-2 has to do with Flying Scotsman and what is the significance of the plaque? Is it boxed and what is the "R" number? Are you sure its a Hornby model as I don't recall any models with £5 coins and have Hornby ever done plaques? There have been plenty of Flying Scotsman Ltds in the past mainly for Beatties and GUS and other retailers but none fitting the info provided.
Happy modelling
Gary
Happy modelling
Gary