Hi Albert,
Which one of the Navy Portuguese lugers should have "MP" on their receiver and not the circle/triangle stamping ???
Hi Vern,
If you let folks know the general area in which you live, you might get a more seasoned collector coming forward and willing to help you in person.
Such a Portuguese Navy purchase can be an expensive one and one we would hope you do not make a mistake.
The folks at PIA have some nice photos of Navy Portuguese chamber markings. Their offereing of the "RP" has some unique 'ticking lines" through the scrolling part of the anchor which I do not know if it is proper or not.
http://www.phoenixinvestmentarms.com/693royalpnavy.htm
Doug Smith and Ken Clark of FGS in Ohio also have some current Navy Portuguese offerings. They have a couple of RP offerings as well with photos of the chamber crests.
Most folks would certainly give FGS high endorsements; especially for a less-experienced collector buying from a retail dealer :
http://www.fgsinc.8m.com/photo.html
Finally, here are some illustrations John Walter has in his book titled "The Luger Book" on page 233 :