I'd bet my money on the fuel pump. There have been various posts with almost identicle symptoms to yours...do a search
Rather than waste your money having it diagnosed, bite the bullet and go straight to the dealer and buy a new pump (£200+) and fit it yourself. You could try cleaning your existing pump but being 10 old it'll probably be a temporary measure.
Or, you could contact
Rufe on here as he's our resident main dealer and can do mail order & discount