A.N.
I have never traveled that long, or with a baby that young (my son was 2 and 6 months old when we have flew), but I still have some experience. It's great that you're nursing, that will be a great way to keep him quiet and happy. Let him nurse and sleep as much as he wants, don't worry about messing up his schedule, the time change will do that for you anyway.
You probably don't want to take messy solids, stick with cheerios or whatever dry stuff you feed your son. I'll be flying in two weeks when my son is 8 and a half months old, and I'll be taking rice cakes. Not too messy, and they keep him entertained for quite a while. Take an extra set of clothes for you and probably two for him, and as for diapers, plan on changing him every two hours on the plane (or more often if you normally change him more). You might not need that many, but at least that way if he gets fussy sitting in a wet diaper, you can take care of it. Try taking toys that you know he will play with for a while, and make sure they are quiet. I hate being around people with kids that have annoying toys, so I wouldn't subject others to that. People may not be understanding if your baby is fussy, or you get up a lot, just let them know you're trying. Good luck!