Re: George VI Coil Stamps.
What you have is a coil join from a "Lightning Roll".
The "Lightning" stamp affixing device was a hand held applicator, used primarily by small companies, for affixing stamps to mail.
Because these were privately used they largely escaped the attention of collectors. As a consequence they are difficult to find, particularly the wrapper or lead papers.
The examples below are illustrations from Stan Kundin's excellent book, published in 2009, entitled "The Vending & Affixing Machine Coils of New Zealand".
Hope this helps,