@mustansir44
What is the update by now?
Some also termed it as "Engine Liner" but usually, people in Pakistan call it as Engine Sleeve, Liner/sleeving if done properly will not do much harm but it depends upon material/Type, is it Ductile iron or Gray Iron or some alloy(cast iron) or some other metal or alloy or something else.
Tensile strength is the core characteristic of Ductile iron while hardness & versatility is the plus point of Gray iron type.
Whatever it is....In Karachi, good machinist always prefer to use good Alloy that should be able to retain lubricant, transfer heat and offer smooth sliding surface for the rings.....................Double check with your machinist before payment