Where to buy private car registration platesWatch
There is plenty of info there, including a link to look through licence plate numbers that are available officially from the DVLA
I have never got a private number plate, or at least, not yet. But once the DVLA approve your licence, you can go to any place that makes them, just make sure that they comply with the standards that the DVLA say plates must follow. Most car part shops, mechanics and dealerships will be able to make your number plates for you, for a price of course
Why they allowed BJ69 as a prefix to go out I have no idea...