Direct Connection "Kit Car" ducktail spoiler

Anyone know if these are being made these days? I once bought one from some fiberglass place in Michigan (I think - it was a good 25 years ago) and all I got was what I'd call the "outer shell". There was nothing inside to mount it to the trunk lid.

For those who don't remember this, it looks a lot like the F-body rear spoiler but it had a row of indented flat spots at the rear lower edge to screw it down to the trunk lid.

EDIT: Found a pic on the interwebs: