Please do not swap the engine, take engine block to machine (lathe) shop and seek opinion from the machinist. Next get the parts list from the USTAAD working on your vehicle and run around pindi saddar area for genuine & oem replacement parts estimate. do some exercise and sum up the advantages & disadvantages ( car value goes down with an altered engine number over the regn book )
add the head bolts to parts list as Guru Xulfiqar recommend new head-bolts for engine rebuild. Head bolts shall be correctly torqued for mating of head & block with gasket to avoid overheating & gaskit burn-out.
clean the engine block water lines with gun brush & oil lines with pressure washer before Ustaad start assembling the freshly machined engine block