Why do you want to wear a helmet during flight training anyway? your flight examiner won't be wearing one, does not instil confidence to anyone. A human head enclosed in a helmet can become a lethal object to the headset wearing instructor or passenger when accelerated in their direction, thats if you can fit inside your R22 with one on in the first place.
You said in your first post - " i am in the first class of helicopter students under the New Zealand loan scheme " what have you failed your ppl seven times or something?, full student loan funding has been available for at least four years now, well from Helifright (NZ) anyway. Thats why there are so many people fighting over the loading jobs, one operator gets 50 - 60 C.V.s a year from CPLs........madness