Since you are interested in String Quartet / Magpies and other birds / Suite for Guitar, here is a list of other items that you may find interesting.
Bartok - Complete String Quartets
New Zealand String Quartet
[ Atoll Records New Zealand / CD - released 21/Sep/2009 ]
Dramatic and heartfelt performances from the 1990s, now reissued on Atoll.
Heenan: Orchestral Works (Incls 'Jack Winter's Dream')
New Zealand Symphony Orchestra / National Orchestra / Youth Orchestra and Choir / various conductors
[ Kiwi-Pacific / CD - released 1/Aug/2007 ]
Heenan holds a special place in the Centre for New Zealand Music's history, as a founding board member and a long time advocate for the establishment of a music information centre in New Zealand.
Aotearoa: Orchestral and string music
New Zealand Symphony Orchestra / Ithaca College Festival Orchestra conducted by John Hopkins and Grant Cooper
[ Kiwi-Pacific / CD - released 30/Jan/2003 ]
One of Lilburn's best-known and popular works, Aotearoa Overture and his Festival Overture are given strong performances by the New Zealand Symphony Orchestra under John Hopkins.