Shouldn't cause any damage but the car will feel skittish when turning and you'll get knoking noises.
Most factors sell them for a few quid. Pretty easy to replace. My normal method for compressing the rubber enough to get the nut on is to jack the car up, wheel off. swap old crap for a new drop link Place a brick under the anti roll bar and lower the car back down untill the rubber compresses enough to get the nut started. jack up again, remove brick, tighten nut, replace wheel, jack down and drive off.