This photo shows one of the five P-3C Orion aicrafts received, from The Netherlands, in the year 2006. It was taken during the 10th of June military parade at the same year. This was, indeed, the first public appearance of a P-3C after their delivery.
If you read spanish, the magazine Fuerzas Militares del Mundo (check its web site) published, in May of 2006, an article wrote by me about the operation of the P-3P Orion fleet and the reception of the new P-3C from The Netherlands.
Actually, since then the maritime patrol and anti-submarine warfare missions have been taken by the two remaining P-3P. The five P-3C will begin their operative carrier in the Portuguese Air Force soon, probably in Beja's air base.
RNLN - PoAF - Version
300 - 14807 - CUP Coastal Guard
304 - 14808 - P-3C-II.5306 - 14809 - P-3C-II.5
307 - 14810 - CUP Coastal Guard310 - 14811 - P-3C-II.5
Source: Ministério da Defesa Nacional (2006)
I suggest the reading of the book The Age of Orion: The Lockheed P-3 Story, wrote by David Reade. Although it is not quite recent (it was published in 1998), it gives us a complete descripition of the development of the project and also about the operation of the Orion around the globe.