Have you tried nissan ?
I had to go though the same thing, I went to my local nissan and they didn't want to help me saying they couldn't find the part numbers. So I rang around and found these blokes
Metro nissan
this is the email for their spares dept.
nissan.parts@nmg.com.au
They're located in brisbane but were willing to send . I just got
these part numbers of them and got them through my local dealer.
INLET VALVE.............13201-08U02
VRS SET .............11042-17U27
the valves cost me $22 ea
and the VRS was $280
Hope this helps