Dick,

  l wish I could reply with an answer, this piece, as you might surmise from the overall condition, is very short on numbers.   I'll post a photo of the receiver so you can see, but the details may be unknowable unless you know of some recovery method.
  What I know is that this has the 2 position tumbler, the plain butt, the early knurling on the hammer, the first markings on the trapdoor and the long wrist stock.  What it doesn't have is an early barrel.  The current one has the proofs from the later years and a rifle sight. And the bore is better than you would expect for the amount of wear on the carbine.
  The "feel" of the piece is what makes me think it had belonged to an Indian at some point.  The saddle ring and bar have been simply removed with no interest shown in 'prettying it up'.  The best I can tell you is that part of the number seems to 6980 or _6980, or 6880. 

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