Nismo 600cc injectors are probably better than the sards and will probably fit the factory fuel rail (no need to upgrade that unless the injectors dont fit money can be spent elsewhere thats more effective)
My engine has arias pistons in it (havent started/finished it yet so cant say how good they are) lots of people seem to recommend CP, most of the jap brands will be fine also but probably more expensive.
Spool conrods (www.spoolimports.com) not overly expensive and good for a lot of power.
If you aren't going to be smashing the thing off the rev limiter an N1 oil pump will do the job, if you are look into the Tomei/Jun options as they are stronger. (Also if your crank doesnt already have the longer oil pump drive get that added if you are running an aftermarket oil pump. Greg from Pro engines in qbn does them for ~$350 fitted)
Tomei poncams will be fine for 350kw. stock cams with adj cam gears will also do 350kw with a bit more boost required than the pon cams.