Welcome to the forum. The full name of that model is actually the .32 Regulation Police. The model was introduced in 1917 around serial number 258000.

That one probably shipped around 1920-21. These prewar .32s (both the round butt and square butt varieties) have been in increasing demand for the last year or two, so I would guess a value in the vicinity of $250-300 -- maybe a little less in some parts of the country, a little more in others.

I shoot modern .32 Long wadcutter match ammo in my .32s; it's a nice low-pressure round that lets you exercise the gun without putting a lot of stress on it.

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David Wilson