If it indeed is only the piston (or indeed if it is the piston at all) the labor to r and r the head not including any work such as a valve job and or valves guides or springs, nor chain and or chain guides is from 750 to 1500 depending on labor rates.

Then there are the cost of the piston(s).

If you can get it cheaply it might be a good deal. The bottom end on benzes is extremely robust and broken pistons are very very rare. Its most unlikely unless a valve broke off and holed it or the cam chain broke and valves impacted the pistons in mass.

If any of those things occurred a good used engine is probably the way to go.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.