Re-ring the engine. This can be done without removing the engine from the car. The cylinder head and sump are removed, the pistons are pulled out through the top of the motor, the piston rings and the bearings that hold the conrods in (conrod bearings or big end bearings) are replaced, and its
put back together.
parts:
piston ring set
conrod bearing set
vrs gasket set (the gaskets to remove and refit the head)
sump gasket
Parts would cost about 2-300.
If you can do it, do it. Otherwise labour is expensive.
But labour would also be expensive for the transplant, and sometimes not everything goes smoothly.