if ur engine is knocking please don't drive it as it will create a whole lotta damage
you will need to replace your bearings and get your rods, crank, caps all measured to make sure they're within spec... you may be up for a new crank depending on how bad the knocking is and new mains and rod bearings... your reconditioner should be able to tell you what size you need
so basic parts off the top of my head
head gasket
rod bearings
main bearings
rings
crank (maybe)
rod on suspect cylinder (maybe)
and make sure in future you have oil in the engine
