Louis,
The printing of the stamps and the perforating were separate processes. The note in ACSC is that when the stamps of this colour were perforated, 5% were perf 14, 95% perf 11.
The 1d is not easy to find, 2020 CV $A325 mint, $40 used. The ½d is $A375 mint and used. The ½d is a far scarcer stamp than the CV would indicate. KJB Stamps on
ebay has both shades of the ½d used for $150. This is a fair price.
If you have gaps you want to fill in your dues collection, let me know. I'm happy to help.
John