You might try the Rolls-Royce Heritage Trust. They hold log cards for many of the Merlin engines produced and that will tell you the Mark/Type of engine and therefore, the likely type of aircraft it was fitted to. The cards occasionally contain the serial number of the aircraft to which they were first fitted.

A chap called Peter Kirk usually did the leg work but not sure he does these days, though I know he is still very involved with the RRHT.

[email]heritage.trust@rolls-royce.com[/email]

Anon.