This Winchester manufactured hammer has the serrated line pattern on the spur and is for the model 64 lever action rifle produced from circa 1948 through 1964. This hammer is in very good condition retaining most of its original blue finish with some areas turning gray from light wear. (file photos)
Note: Winchester pre-64 model 64 lever action rifles with the following calibers and serial numbers have been observed with this part
30 WCF: 1375541
32 Win Spl: 2063562