there is absolutely NO POSSIBLE WAY for anyone to give you an answer.
your caloric needs are 100% unique to you. factors that affect your caloric needs include: your body type, body composition, pregnant/nursing, age, activity level, night owl/morning lark, married/single, live in a house or apartment, walk/drive, automatic/standard shift, and so on.
go ahead and mess with the calories - baby won't suffer because milk production is given top priority. as long as you're taking your nutrients and supplements, the milk will remain top grade.
even that "add 500 calories because you're breast-feeding" is not cast in stone. some women need more, some need less. obviously, a baby who feeds long and heavy will require more milk production than a baby who just basically nibbles throughout the day.
personally, i would leave off
weight loss until you're more stabilized. maybe it's just not realistic or reasonable to engage in a physically demanding lifestyle with a new baby to cope with.
if you must, though, start by dropping 100 calories for two weeks and see what that does. then drop another 100 calories for two weeks and so on until you see things happening. you don't necessarily need to eat less - just add ten minutes of intense cardio 3 to 5 times a week.