Hi Rafster!You can pick up the Profile Publications on ebay, you may have to compete to get the ones you want though...
Very little info on:
Supermarine Spitfire I-III
More text and the above posted photo RJ Mitchell. A life in Aviation - The Supermarine Spitfire - Design
Have you used a Google search for Supermarine Type 224?
You may need to use Google's cache feature for the text for some links as the information is no longer on the website but Google has the text in it's information memory/disk stores.