Looking to the Uberti catalog I think the exact model of this revolver should be "Richards Mason Navy 1851", 38 special caliber and 5 1/2 barrel.
Ah so... very true my friend.
The "Richards Navy 1851" doesn't have the cases extractor on the side of the barrel and it only comes with 7 1/2 barrel
Once again, you are absolutely correct. And exactness is a virtue! So I must go back and correct this gross error I have perpetrated upon this forum!

I confess! Mia Culpa, mia culpa, mia maxima culpa (that's a Catholic thing...) Here's the truth: My handgun was only manufactured by Uberti!
It was actually marketed by

as their 1871 C. Mason Revolver - Navy Style! Their catalog can be seen here:
http://www.taylorsfirearmsstore.com/1871_mason.htm BTW, I believe the revolver shown is the "Army" style, hence the round barrel.
I swear fellers, There was no intent on my part to mislead anyone! I just thought everyone here would be familiar enough with the words used, i.e. Navy vs Army for me to take a little descriptive license!
Which reminds me, I got to post another pic with this revolver and my '51 Navy side by side...
OH!! welcome to GBO and the forum BD!

and now it's your turn!