There was a Jack Allen who was active in the Hawkes Bay area.
He owned the DH60M Moth ZK-AEJ pre-war, from October 1936 until it went into RNZAF ownership during September 1939. He lived in Wairoa, but based the aircraft at Hastings.
Post-war. he had Tiger Moth ZK-AQW from November 1947 until selling it to the Gisborne Aero Club and taking ownership of Tiger ZK-BBL in August 1952.
He also reacquired the Gipsy Moth ZK-AEJ in August 1950 and kept that until his death in the mid-1960s.
His executors then sold the Moth to Gordon Reader in 1966.
Based on the above, I think your photo of ZK-AOW is actually AQW.
If interested, you can contact me on pvlewisnz (at) gmail.com
Cheers, Peter Lewis