I cannot help with size, but I'll tell you what I did. I replaced all mine. I wound up using a torch to heat up the glass enough to fracture it. Then a putty knife, heated by the torch, to get behind the glass and remove it. Then cleaned up the adhesive; went to a glass shop, had them cut to measure. I had them bevel the corners to a radius of a dime. I them re-mounted the mirrors using a mirror adhesive (so as to not attack the silvering). I taped them in place and let the adhesive set up two days. Then I used an almond latex caulk to seal all the edges so moisture would no longer get behind the mirrors. Wear gloves!