Strange... I seem to have a copy of all (?) Bits & Bytes up until it became New Zealand Computer in April 1998!
I can certainly post you the September '83 issue. Just send me the details.
I am currently deciding what to do with them all as we recently moved to Milford, North Shore and my office is a LOT smaller!
Any one interested in them as a set, please contact me.
I also have a duplicate set up to August 1983 in the official B&B binder.
(the original B&B contributor)