Re: He doesn't "regulate" his feeding, so how much at a meal?
I don't see any reason to be concerned about your baby's weight- according to this chart for breastfed baby boys, he's right at the 50th percentile. Gaining at a slower pace after 6 months is totally normal- all that calorie-burning motion!
I would nurse him as much as possible, and as sixtyearplan suggested, offer 3-4 tblsp of food 3 times daily. If you're at all concerned about his weight- and again, I don't think you should be!- then I would concentrate on the high-cal solids (beans, whole-milk yogurt, meat, avocado) instead of low-cal fruits and veggies.
Coolest thing my big girl said recently: "How can you tell the world is moving when you are standing on it?"
Coolest thing my little girl sang recently: "I love dat one-two pupples!"