bent valves but the surface of the pistons had indentations from the valves about a half inch from the piston rings on all pistons

i bought this car and the owner told me it might have bent valves because the timing belt snapped. i bought the car anyway hoping to replace the cylinder heads. after looking at it i did see that the valves were bent, but the surface of the pistons had indentations from the valves about a half inch from the piston rings on all pistons. would this cause a problem in the drivability of the car? Is this a lost case or do you think i have a chance to revive the vehicle? pistons are moving up and down the chambers with no problem. please give me your expert advise.