Hake brushes are available at most of the larger artist supply stores.
Having never been "down under", I must assume that New South Wales has a
large art store, check with a painter or lithographer in the art
department at UNSW . If not, mail order is the way to go. In the United
States, I get them from the Daniel Smith Company out of Seattle
Washington (north west Pacific coast). The list them in the 'Sumi
Materials' section and prices range from $1.37 USD for a 1" brush to
$5.34 USD for a 5 1/2" one.
Thier address is:
Daniel Smith Company
4150 First Avenue South
Post Office Box 84268
Seattle, Washington 98124-55568
Voice #206-223-9599
Fax # 206-224-0404
Hope this helps
Gordon
Phoenix, Arizona