yep, that's the correct part number. if parts or cash is scarce, you can reuse the old spring washers like i did. i only ordered enough parts to do the job as per the bulletin/service manual. I didnt realise the Kawasaki nut was *shorter* til they arrived, so reusing the old spring washers was a quick on the spot solution to get the car buttoned up and off my mate's driveway.
finding a castellated nut of OEM grade with identical threads was enough of a challenge so i wasnt going to let a bunch of washers ruin my day
good luck guys! just remember to torque the nut to spec, then budge it clockwise with a breaker bar til it reaches the next slot and punch the cotter pin thru it.
the cotter pin MUST be very snug so you might have to experiment with how you fit it (rotate, hold, hammer, etc). i highly recommend getting a few extra pins because they aren't as easy to fit properly due to the hub interfering with any direct strikes.
It MUST be fitted snugly!
Part numbers (including OEM components required for those attempting the official Nissan fix):
nissan cotter pin: 40073-0L700
nissan big nut: 40262-1CA0A
nissan adjusting cap: 40263-1CA0A
nissan spring washers: 40037-1CA0A
M77 grease: get it from Honda