i would hold out on buying new bearings untill you have your crankshaft reground, there is a required clearance between the bearings and journals, also possibly cheaper to buy 2nd hand.
I did spot an ebay company a few months ago who collect and also supply the required bearings. i'm in noway affilliated with the company, i was looking into rebuilding an engine alittle while ago.
http://www.ebay.co.uk/itm/CRANKSHAFT-GRINDING-NISSAN-300C-300ZX-350Z-MAXIMA-NAVARA-3-0-3-5-V6-ALL-YEARS-/161920955252?hash=item25b33db374:g:diQAAOSwZjJU8DOd