1988 MAZDA MX6 Structurebodydoor Problems

INITIALLY WHEN THIS PROBLEM OCCURRED, I DISCOVERED THE DOOR HANDLE MECHANISM IS MADE OF POT METAL AND NOT OF A VERY STRONG NATURE FOR THE FREQUENT USE IT GETS. CHECKING WITH THE DEALER I FIND IT WILL COST $300 TO FIX. TO SAVE MONEY I RESEARCHED USED PART PLACES. I DISCOVERED THIS IS A WIDE SPREAD PROBLEM AND DOOR HANDLES ARE RARE TO COME BY AS MOST ARE ALREADY BOUGHT UP. I HAVE SEARCHED NORTHERN AS WELL AS SOUTHERN CA, AND WILL NOW TRY IN TX. I FEEL THIS IS A SAFETY ISSUE BECAUSE MY 2 YEAR OLD WAS LOCKED IN THE CAR THE OTHER DAY AND THE HANDLE OF COURSE BEING BROKEN WOULDN'T OPEN. LUCKILY I WAS ABLE TO PUT SOMETHING DOWN THROUGH THE GLASS TO OPEN IT FROM THE INSIDE. THIS IS OBVIOUSLY A DEFECTIVE PART, IS THERE ANYWAY TO HAVE IT FIXED BY THE DEALER?.