Plenty of international manufacturers offer UK 13-amp sockets for round 60 mm back boxes. I found Berker (a Hager subsidy), Gira, Merten, Jung, Legrand and Vimar with a few minutes of searching the internet. Some include accessories only used in the UK, Ireland and other countries following UK wiring methods, e.g. fused connection units. So yes, you could easily fit round 60 mm back boxes in your house and perfectly normal British sockets that comply with any regs you might come across. The only downside is the availability of spares in case something breaks. These sockets are not something your local electricians carry around in their vans all the time.
Note that most European sockets have been square since the 1960s, even though the back boxes are round. A select few manufacturers offer round sockets for nostalgia's sake, usually at fairly substantial prices. Belgium and France use a mix of square and round boxes with the same 60 mm fixing centres, Italy mostly favours rectangular American back boxes, the Swiss and the Danish each have their own, wholly incompatible national standards. Austria uses round 70 mm back boxes with 60 mm fixing centres or octagonal gangable 70 mm back boxes. All other European countries I know of use round 60 mm back boxes.