Here is another PNC I picked up on the "Trade Me" auction site in New Zealand. The best thing is that I only paid AU$6.00 for it. Was VERY surprised when I found I had won it for that price.
Trade me description:
On offer in this auction is a New Zealand 1974 Commonwealth Games dollar in a Philatelic-Numismatic-Cover postmarked and registered on the day the coins were first issued -- 30th October 1972 -- and backstamped at the Sydenham PO on that day.
PNCs or Coin-Covers are covers which contain coins of significance both sides of which are visible through holes cut in the outer cover. The coins are first fitted into a card to hold them firmly then covered with a plastic sheet to protect them. After the stamps have been affixed the cover is postmarked with a date that has meaning for the coins or the stamps or both.
Note: Cover offered here is #544 of 675 issued most of which were sold in the USA.