Want to make sure to get quality parts?
* Make sure the bearings are Datsun-spec F77 tri-metal and not cheap alumninum bearings
* Don't get fel-pro printoseal (ps) head gasket. Other Fel-Pro lines are top-notch

Your best bets are genuine Japanese brands, but american suppliers are usually good like Clevite 77 for bearings, Beck/Arnley is almost always packages Japan brands, Moog usually repackages Japanese parts ... in other words most stuff that RockAuto sells is OK, and the less expensive closeout parts are usually best. The cheap chinese stuff is becoming the new normal "regular stock"