Yep... But sadly, the nice cast number on the side of the block turns up nothing. The number that matters for identifying the specs one the engine was stamped behind the distributor. That number is so worn down, I can only make out the first letter of F. That does confirm that it is from a Spitfire or Midget, but doesn't get me any closer:
FC (HE=9.0:1, LE= 7.0:1), 1147cc, Spitfire MkI
FC50001, 1147cc, Spitfire MkII
FD (HE=9.0:1, LE=7.5:1), 1296cc, Spitfire MkIII USA
FE (8.5:1 for emission controlled), 1296cc, Spitfire MkIII
FH (9.0:1), 1296cc, Spitfire MkIV,
FK (8.0:1), 1296cc, Spitfire MkIV USA
FM (9:1-world, 7.5:1-US, 9:1-US in 1976), 1492cc, Spitfire 1500 (1973-80)
FL, 1492cc, Spitfire MKIV/1500 Sweden
FP (9:1-world, 7.5:1-US, 9:1-US in 1976), 1492cc, 1500 MG Midget (1975-79)