which is damaged ? the pipe between the engine and the cooler or the pipe from the cooler ? the pipes are removable, just undo the small allen bolt at the flanges, and pull the pipe away from the flange. replace the o rings if they get damaged while removing.

Turns out the oil cooler itself is also rusted which is why removing the pipe will damage it. Does anyone know what part is needed to completely remove the oil cooler?

There is a bracket type thing behind where the oil filter goes, remobe the oil filter and the remove the square box brackt thing and just replace the oil filter again minus the oil cooler.