You are looking at a Chevy 10 or 10 1/2 inch clutch flywheel from a 64 Chevy Impala with 327. Its cast # 3791021 & dated F244 which is June 24, 1964 for the late 64 or early 65 model year.  Correct flywheel for most 6 cyl. & SB Chevy V8 in the 60s including 64 to 74 V8 Nova (even L79), 67 to 69 Z/28, 64 to 72 Malibu, 63 Corvette, etc. The surface shows only light ware and is usable as is. No heat cracks. The 153 teeth show only light ware and are OK. Hard to find date.