On August 13th, 1998 Australia Post released a series of 5 stamps and 3 postcards to honour the work of Leunig.

The stamps are also available in the Leunig Prestige Collection, a booklet also containing a selection from his collected writings and a set of stickers.

These itmes are no longer available from Australia Post but if you're keen, try philatelists or check the internet auction sites.
 
 

"Heart"

"Messenger"

"Teapot"