The best M-1 Carbines are the USGI ones.
If it's made by the following, then it's USGI:
Inland Division
Winchester
Irwin-Pederson
Saginaw
Underwood
National Postal Meter
Quality Hardware
International Business Machines
Standard Products
Rock-Ola
Commerical Controls
The majority of the commerical made M-1 Carbines are less reliable than the USGI M-1 Carbines. Auto-Ordnance (Khar Arms) is the only commerical manufacturer still making M-1 Carbines.
You can get a USGI M-1 Carbine for about $500-1500 depending on condition.
You can get a brand new Auto-Ordnance (Khar Arms) M-1 Carbine for about $800-1000 depending on configuration.
You can get a used Universal M-1 Carbine for about $400, but you may spend more time trying to fix it than shooting it.