For the passenger door ~ Try zmanalex, RS Shades, R35LEE, Clark Motorsport and anyone else you can find on here in the for sale section that says they are stripping a 350Z.
I think the chubby ninja is also breaking his old 350Z after he crashed it but not sure if his doors are in good shape ~ think he did a pretty good job of denting almost every panel poor guy.
The front bumper is such a personal taste though imo and also depends on your budget. I personally quite like the front bumper that bizz runs on his drift car which is available from Tarmac Sportz.
Link: http://www.tarmacsportz.co.uk/GB/350Z_FRP_NISMO_V3_STYLE_FRONT_BUMPER/350V3FRPFB_.aspx