The problem is finding original Nismo parts is rare and expensive. I think Alex was selling original bits a long while ago, but then I could be talking crap.
You could get a replica kit at a fraction of the price, and yes you could get fitting issues, but that's why new original kits cost what they do. My front and sides are copies, both made of fibreglass, but not yet destroyed anything on a speed bump, and I'm lowered 25mm.