Bagpiper: Colt first made 1911s for Argentina during the 1920s I believe, and the model was referred to as the 1927 as it ahd a target hammer and knurled trigger face, etc. The Argentina took over production on Colt equipment that Colt sent to Argentina and the Argetines called that the Modelo 1927 - It was marked in Spanish with Pistola 1927 Ejercito Argentina, Calibre 11.45mm - meaning (translated loosely) 1927 Army pistol. Those were made for the Army. I do not know of any made for the Navy - as that is what 'Marina' means, Navy.
However, what we have wit these pistols is two makers, Colt early on and they may have stamped it as you have seen, but then Argentina took over production and their stamping was more consistently heavier and blockier than the Colt stampings.
It this is a Colt made or Argentine made pistol it should not have a Cxxxx serial number. Those C-prefix serial numbered pistols were American commercially made Colts.
Production of the Argetnie pistols would not have been in the 1915-1920 period, it would have been later in the 1920s - 30s.
Parkerized - no, I think they would have been blued.
C- prefixs and Government Model don't mix - the C-prefixes were commercial, the Government Models were government models.
If it looks too much 'newer' it is probably bogus. And $800 is too much. HTH. Mikey.