When I spotted the thread title, the first name to come to mind, for me anyway, was "Trevor."

The first Trevor I ever met in person (here in the states) was a coworker who had been born in South Africa. Not England by any means, but more-or-less "British" from the US standpoint. (He was certainly of British ancestry ~ not a Boer or an African.)

While I had never previously known a Trevor in person, I did recognize the name as a boy's/man's name.

At my next job, I had an employee named Trevor, but this was (and still is) a female Trevor. Very attractive, and very aristocratic, from a wealthy and prominent family. Made me wonder if upperclass Brits named their daughters as well as their sons Trevor, or if this was a strictly American affectation ~ ??

One name mentioned only briefly and obscurely in one of the preceding posts struck me as just the kind of quintessentially British names LH was asking for:

Rhys.