Brembo makes stock-style blanks for at least the rears on the more recent P11s, but I don't know about fronts. Once you have the blanks (which have a higher tinsile strength and are often thicker than OEM to start with), you could have a local machine shop score or drill the rotor for you. Beyond that, I don't have any ideas.
If you had around $1800 US to spend, you could have Brembo's full-race brake kit for the Primera, which is a bolt-on affair.
Bad news if you're after drilled or slotted discs - you can't get them in the UK at the moment - I just tried. Nobody does the 280mm discs, only the smaller ones.
You can get plain discs (EBC I think?) but nothing more....unless you are super rich and want a large brake upgrade package!!