Zitin if you want plans you have 2 options, either the RAF Museum at Hendon, they have nearly all the Supermarine sheets you'll need, but it will cost a fair penny.
Or if you just want some CDs of the MkV plans then contact the guys over at the Y2K Spitfire project in Canada, Harold will be glad to sell you the CDs, and the money goes to helping put Y2K back in the air