After 19 years under the hood the original motor mount heat shield covers were looking pretty shabby.
I've looked around for a while and had no luck finding OEM replacements. I then came across D & H Heat Technology of Mooresville, NC
http://www.koolmat.com/index.htm who do a lot of Corvette heat related products. I sent them one of the mounts and heat covers and they came up with a C4 Corvette motor mount cover replacement to their own design using a more modern silicone/fiberglass bonded heat shielding material.
I am very pleased with the way these turned out.
If you are also looking for replacement motor mount heat shield covers I highly recommend this company. They have the paterns now and can fix you right up with a pair.