There are multiple new McKern works recently published by Wirripang. Some are for choir, some for organ. They can be seen on the Wirripang website:

http://www.australiancomposers.com.au/authors/brett-m-mckern

Or on the new library acquisitions list of the Australian Music Centre:

http://awscdn.australianmusiccentre.com.au/documents/acc01_15.pdf

Or on the list of McKern works at the Australian Music Centre:

http://www.australianmusiccentre.com.au/artist/mckern-brett