hey, welcome to the forum.
Stroker kit, you can buy the toda or spoon stroker kit, they both have great quality and results.
For the header, if you buy the stroker kit you can get a 4-1 header, for the b16b the 4 2 1 gives the best results, also you can get a tri y design header and get excelent results also.
For the ecu, i recommend you to buy a custom map, and a chipped ecu, it's cheaper, and if you have access to a dyno it'll be easier.
The best camshafts for the b16b in my opinion, the toda spec b are the best. If you install this camshafts, you'll need a thin head gasket and to shave off 0.20 of your head, because you'll need more compression.
I have a itr 4.78 final drive installed in my gear box, by far is the best mod i got! elmo has a 4.9 final drive and he says the car performed a lot better.
Good luck! where are you from?