Hello, welcome to the forum.

Unfortunately there is nothing written on a piston that will identify it to an individual aircraft; the information is of a much more mundane nature relating to the piston itself. On bomber squadrons aircraft would have engines changed, rather than pistons changed, if there was any problem with the engine core; only the engine serial number would be linked to the aircraft serial number.

Your piston is a ‘Merlin’ piston but identical pistons were used on a large number of British aircraft; the Lancaster, of course, but also the Halifax bomber (often a shot-down ‘Lancaster’ will turn out to be a Halifax), some versions of the twin-engined Wellington, the Mosquito and some versions of the Beaufighter (night-fighter) could be possibilities?

What I can say is that it is a Rolls-Royce Merlin piston, as opposed to a US-built ‘Packard’ Merlin, so that (usually) rules-out any Lancaster Mark III if it is indeed from a Lancaster.

The information stamped into the piston is the weight in pounds, ounces and drams (LBS OZ DRS) and the part number D10952/3. The other stamps are probably material specifications or batch numbers, plus the usual inspection stamps, although the compression ratio (6:1) and the piston manufacturer are sometimes present.

Do not give up hope of identifying an individual aircraft; almost all RAF bombers that came down on land during the war are well documented. The crucial information required would be the location where the aircraft came down and, most crucially, the exact date.

One source of information, if a crash location is known, may be the local church; if some of the crew were killed (and unfortunately they usually were) they may have been buried in a local church graveyard (but then moved after the war)? Church records may still have details of names and dates?

I wish you luck with your efforts and will help wherever I can.