fenugreek would be a god next stop, or depending on wher eyou're at, domperidone (rx). most of my clients had great results with fenugreek, but the ones that didn't were helped with an rx.
there is also a tincture you could try- one of the ones from
Herbs and Herbal products for pregnancy, birth, nursing and breastfeeding, to increase breast milk, Motherlove Herbal Company - Motherlove i'd likely go with either the "more milk plus" or "more milk special blend" depending.
how much does she weigh? eating 9 oz at one time, at only 4.5 months sounds like quite a bit.
also, you could try to use massage and breast compression to try to help get more milk out better while pumping.