They look like 'L's, but they are '1's. Winchester has never offered an explaination for these odd-looking numbers, but does confirm that the stamp represents the digit 1.
With the serial number that you have provided,your Winchester model 88 lever action rifle was made in the year 1962.
with the serial number that you have provided,your Winchester model 1873 lever action rifle was made by Winchester in the year 1886.
With the serial number that you provided,your Winchester model 1897 pump action shotgun was made by Winchester in 1924.
With the serial number that you supplied,your Winchester model 1912,pump action shotgun was made in 1961.
With the serial number that you provided.Your Winchester model 88 lever action rifle was made in 1960.
With the serial number provided,your Winchester model 9422M .22mag lever action rifle was made by Winchester in 1974.
With the serial number that you have supplied,your Winchester model 88 lever action rifle was made in the year 1966.
With the serial number that you supplied,your Winchester model 1912 pump action shotgun was made in the year 1916.
With the serial number that you have provided,your Winchester model 1912 pump action shotgun was made in the year 1923.
With the serial number that you have provided,your Winchester model 88 lever action rifle was made in the year 1959.
With the serial number that you have provided,your Winchester model 54 bolt action rifle was made in the year 1935.
Your serial number indicates that your Winchester model 12 pump action shotgun was made in the year 1942.