Complex sentence: Each 1972 Regency owner received a distinctive sterling silver key ring as a gift, if ever lost the keys could be dropped in a mail box, and Tiffany's would return them to the owner.
Split into simpler sentences: Each 1972 Regency owner received a distinctive sterling silver key ring as a gift. If they were lost, the keys could be dropped in a mailbox, and Tiffany's would return them to the owner.