9 grains of Unique is Rocky Raab's universal .30 cal plinking load, though he goes up to 10 grains in the longer .30-06 and magnum cases. 9 will work fine for you.
You also have the option of loading with Trail Boss to keep the case better filled for the most consistent ignition and MV. Plus it burns cleaner than about anything else ever made. 70% to 100% full up to the bullet base, but not compressed. Those are IMR's instructions