Yes 0651 engineIs that with the OM651 engine? I found diesel around a couple of the injectors on mine a few months ago so I had all the seals replaced, but it does have over 120k on it. No idea if it's normal at 67k (assuming it's the same engine).
Parts were cheap. I have no idea what the labour rates are like in the UK, but I wouldn't imagine it would be too costly if you tackle it early enough.
What about the car…Just had my seals and rocker gasket changed £500 all in.
Then I suggest trying to source the plastic connectors that attach the fuel return line to the injectors before you start - apparently mine had become brittle and broke when the mechanic tried to remove them.Yes 0651 engine