Thanks. I think I’ve found it. 91.880 (d) Although elsewhere it states experimental aircraft not to be used for hire or reward.
CIVIL AVIATION SAFETY REGULATIONS 1998 - REG 91.880
Experimental aircraft--kinds of operations permitted For the purposes of subparagraph 91.875(2)(d)(ii), the
kinds of operation are as follows:
(a) taking the
aircraft to a place where maintenance on the
aircraft is to be done;
(b) taking the
aircraft from a place where maintenance on the
aircraft has been done;
(c) testing the
aircraft after maintenance;
(d)
flying training (other than for the issue of a
pilot licence);
(e) practice in flying the
aircraft;
(f) carrying out a
demonstration or test of the
aircraft for sale;
(g) delivering the
aircraft to a person under a contract of sale;
(h) for an
amateur-built aircraft or a
kit-built aircraft--flying training given to the
aircraft's
owner.