10-50 USD or so
Old catalogs
if it's a 380 caliber then made about 1924
Can't tell the caliber from just the serial number.
Impossible to tell from just the sn. if you found the serial number, you will be able to find the caliber of the pistol somewhere carved in the metal.
You can call Colt and give them the serial number or you can look it up in the Blue Book of Gun Values.
1911
No way to answer without the serial number.
100-10000 USD
@1914
@ 1972
Value will depend on exact configuration, overall condition, finish, box, manual, accessories, serial number, barrel length, etc.. Range could be from 25 USD to multiple thousands of USD.
Stevens was in business from 1864-1950. They did not have a "pocket pistol" model, but DID make a "pocket rifle" model from 1869-1916. Am aware of no specific production data based on serial numbers.