I have the opinion that these trains are from an Englisch brand. LNER is one of the older Englisch mainline holdings. Western courier could also point in that direction as “great western” also is an Englisch holding. Modeltrains where made by Hornby (meccano) and some smaller ones (Heljan,Lima etc.)
Do you have pictures from them? Could help a lot!
The red diesel locomotive, D1062 is a Class 52 “Western”, the prototype was used on Bristol, and Penzance trains, D6103 is a “North Briti***ype 2”, of which the prototype was used in Scotland. The Steam loco was a shunting locomotive used by the “London and North Eastern Railway” in the years before 1948.
The models probably were made in the early 1980s, and are not particularly rare or valuable. They are strong and reliable models, and spares can easily be obtained to keep them running. They would make a good start for a layout, if that’s what you want. They would not, in real life, have been seen running together, but that’s not a problem unless you want it to be.