Colt SAA-info needed

[tcp]

Last week a customer of mine showed me something he thought i might be interested in. He pulls out a SAA and the first thing i notice are the hard rubber grips with the pony on them. The story is that this guy received this gun from his father who got it from his father. Other than that the guy didn't know much about it other than it might be valuable. I told the guy i'd look into getting him some info on it and tried my google-fu, sad to say i'm just above a white belt. I was wondering if some of you guys/experts could help with any info or where i could look myself.
Here's the guns info.
It was all blue, dont know if it was reblued or original, but the blueing looked really good with some areas of rust.
It was marked 38 colt on the barrel,which was 4 3/4".
Serial number 289655, first generation?Manufactured around 1907?
Black rubber hard grips.
On the frame "Pat sept 19,1871" then two dates "July 2, 72 Jan 19, 75"
Also had "Colts Pt F.A. mfg. co." "Hartford, Ct. USA"
Something else i did notice was that there was no half-cock when i pulled back the hammer, could it be broken?
Any info would be appreciated. Is there also anything else i should look for on the gun?
Thanks

[Alan Block]

I went to my handy DGW catalog

The serial number places it in 1907 - years production was 16000. Halfcock notches are fragile and could have easily broke. A new hammer could be bought, but any replacement parts would detract from the value.

[tunder]

First step is to get a factory letter from Colt.

http://www.coltsmfg.com/cmci/historical.asp

Factory letter is about $100.
Then you can see if the gun is anything special.
I picked up a Bisley several years ago that increased in value simply due to having the factory letter.
First Generation Colt SAA's fall into the desirable collectible category but repairs with old stock Colt parts is generally acceptable.