As (possibly?) mentioned somewhere in this thread, the CS-1 revolvers had a black plain ramp front sight blade and came with a variety of stocks. Most of the issued guns I have seen had Pachmayr Compacs with the bottom cutout for seeing the SN. Also, there were a fair number of production overrun guns, so if your goal is to have a USCS issued gun there is no way to tell short of a history letter.
Having said all that, $800 is not a bad price for a CS-1 of either barrel length, and the front blade can be replaced. May want to buy it before the seller jacks the price up even higher
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