New 54540 Cylinder Block for 2.6ltr VB6 series engine with engine no's LB6B/E & VB6B/E, 

Note: on an Aston Martin or Lagonda built from 1949 to 1959 the engine number is on the timing cover as the cylinder block was considered to be a consumable, as such a new block isn't a disadvantage to the cars provenance, in fact it enhances it.