Body numbers do not tie in with chassis numbers.
Chassis number 1476XXX is from March 57(476XXX is from Apr / May 53) - this should be on your VIN plate (above the body number as you mention) and also on your chassis on the centre tunnel under the rear seat - this is the 'serial number'. Body number 477XXX, as stamped into the body itself, is from February 57. Engine number 276XXXX is from January 59 so would not be the original one from you car
This page gives you everything you need:Type 1 VINs