I think Arlen Ness do kangaroo leathers but dont discount Alpinestars, Rev'it, Frank Thomas and a few others as they do some superb leathers and to be fair boots and gloves too at reasonable prices.
What sort of Arai you looking at?? Ive got the Corsair Haga 41 lid and its amazingly light and visibility is good.
I personally use:
Arai Corsair Helmet
Rev'it GT Corse 1 piece leathers
Frank Thomas leather/Carbon fibre gloves
Alpinestars SMX plus boots
Check some of those bits out as i think they are really nice kit....