L.,
The first thing to do would be call a certified lactation consultant and get some professional advice ASAP. The ones at Morton Plant in Clearwater are FREE (whether you delivered there or not) and can provide helpover the phone or set up an in-person appt. ###-###-#### There shouldn't be any reason she can't help you set up a good pumping routine to be able to pump enough out for one bottle a day.
Are you immediately after the first morning feedings? The first couple feedings in the morning would be the best since you produce more milk in the am. Are you consistentlypumping at the SAME time every day? You body gets used to the time of day that it thinks your baby needs the extra and makesit for that time, thus consistency is key. Are you pumping during the feeding that the baby gets a bottle? I would also continue to pump then, otherwise your body is redcing it's production at that time, thinking that the baby doesn't eat then.
Is there a reason the baby MUST drink from a bottle at the bedtime feeding? If it came down to choosing between nursing and giving formula, you might consider having him nurse. Nursing draws so much more milk out and manitains production much better. As soon as you start replacing the need for your milk with formula, your supply will drop since you are then actually nursing less.
Have you tried taking fennugreek? You can get it at a health food store and can take 3 capsules 3x a day and with most moms it really increases supply within a short time. You could also drink coconut milk (mixed with a fav drink or smoothie too!), red-raspberry-leaf tea, and eat oatmeal....plus drink LOTs of water to stay really hydrated.
I think once you connect with a lactation consultant you will get on the right track to maintain all the milk you need to keep nursing. Your little one is only 7 months, so all of the consultants help will be very supportive for months to come :-) Best wishes.