I have had a slight slow coolant leak at front tip of head gasket on a V8 about a quart every 300 - 400 miles. I just keep adding antifreeze. No oil in antifreze or air bubbles and engine runs normal or sightly below. Would a head gasket or radiator seal work?

Replace the head gasket--stay away from radiator and head gasket sealants. If you are going to do the job, do it right. Be sure to examine the head for warpage, too.