need advice on fuel pressure regulator

[matt31]

just put an rb25det in my r31 and during the conversion the fuel pressure regulator got damaged and has a leak, now while driving at half throttle everythings fine but when i floor it like sort of cuts out and in violently, so my first question is would the leak on the fuel pressure regulator be the problem or could it be something else,

secondly the fuel pressure regulator will need to be repaced so should i get an aftermarket one while im at it or look for a second hand stock one, and if aftermarket what one?

[rb26dett]

nismo one would bolt straight on. not that expensive either.