you look to have got most items well under control
major items missing
flask and butties
bucket load of patience and enthusiasm
seriously though when you start to race look at what the local guys have/use/need more than likely they will all try to help as we are always short of newcomers to the hobby
good luck for september ( choose a car that has good spares and back up reputation all the major players wil be ok ask the locals where you intend to race most its a good pointer
regards dave