My boys are/were breastfed, but they started a sip cup early, like 4 months. We also practice extended nursing so the boys didn't really get cows milk unti lwell past thier first b-days.
I guess since we breastfed we aren't really 'ounce-obsessed' and just give the boys what they want to drink for milk. I consider milk a meal, not a drink, so they get milk with dinner, and water the rest of the day. They don't drink alot of milk and thats ok with me, I'm not going to force it on them just to meet some 'requirement'.
Remember taht cheese, yogurt, cottage cheese, etc also count as thier dairy intake.
As far as bottles go, it would be in his best interest to get rid of them as soon as possible. Sucking on bottles is bad for teeth, and also bad for the jaw. It forces the jaw out to suck the liquid out, and the milk also pools around the teeth. Replace one bottle every couple days with a sip cup of whole milk. He won't drink as much milk from a cup, so don't expect him to. offer it with meals and give him water the rest of the day.