1973-1979 rear speaker covers
 

I believe that these have two applications:
1) factory install for cars with rear speakers; 1973-1979
2) GM aftermarket rear speaker add-on; 1970-1981

The 1970-1972 cars with a factory optional rear speaker had a rear dash with a perforated top layer of vinyl (think 'comfortweave');
After 1972 the cars all received a plain rear dash cover, but cars with the rear speaker had one side cut out for these covers.
If any 1970+ car was built without a rear speaker/speakers, GM sold a kit for owners which permitted installation of a rear speaker (or two depending on the kit). The kits had one or two speakers, with a corresponding speaker cover, and the necessary loom to get radio signal to the rear dash.

These are to the best of my knowledge not reproduced, and they were tough to find - twenty years ago.

I had recently been made aware that the original 1980/1981 rear speaker covers were a different pattern.

Asking $30/ea ($60 for the pair) plus shipping - odds are shipping would be exactly the same for one or two.

I am willing to break up the pair, or sell them together - I believe I have another one if someone only wants one;
I put these two together because they appear to be the same colour, and most people these days seem to be putting a pair in the rear dash.

The third image is of NOS GM replacement speaker covers which was listed on eBay this past spring (not to be confused with the accessory kit with all the parts).

bump!