See my earlier post about saving those programs that NBC had trashed by about the mid 1970s. Most of Ernie’s work got chucked as well and little of it survives today.
Plus he was married to the lovely Edie Adams; in the "making of" materials on the DVD of "It's a Mad, Mad, Mad, Mad World", some voice noted that the movie was her first role after Ernie's death. Kovacs had some tax problems before that..