1851 Navy; Great choice!
Brass frames? No.
.44 in a "Navy"? That is an oxymoron. .36 is "navy' size. The .44 was the "Army " calibre, and was never chambered in the 1851 platform, until the repros arrived. When Colt was able to improve their product with better steel, they used the frame from the '51, with the .44 cylinder, but used a longer grip and the newly developed creeping rammer. The result was the most graceful revolver design EVER, the 1860 Army.
(The exception to .44s in brass is our Pard PalladinUK, who lucked into a brass,.44 "Navy", for TEN BRITISH POUNDS!!!!!)