Ashley,
The modern navy series is an interesting story. Although I can’t buy them locally, I have collected most of them. I noted that there was a limited edition set of modern RN ships with the ships name and limited edition cast into the underside of the models. Pennant numbers were also added. I chased up finding these models for my collection but was told that they were no longer in production, I eventually managed to get a complete set sent from Hong Kong by Charles Shave, he is the new owner of Triang Minic Ships
The production run was supposed to have been 500 complete sets but quality control caused only 350 sets to be released. You can find odd limited edition models that were intended for the complete sets and these have been released for sale individually, but they are obviously rare as there would have been no more than 500 made.The complete sets come with a numbered certificate of authenticity. These models should become much sought after in the future!
As well as the RN ships, there is a range of Modern US navy ships as you mention and also four modern merchant vessels.
Regards Alan