Mfgs of USGI M1 Carbines and the quantity they produced are:
Winchester 828,000
Inland 2,632,000
Saginaw 517,000
Rock-Ola 228,000
National Postal Meter 413,000
IBM 346,000
Underwood 545,000
Quality Hardware 360,000
Standard Products 247,000
Irwin Pederson 4,000