They do indeed look like Oxford Cream Leather Monogram seats, I have a set fitted to my ZT 180 SE Sports Auto, but as has been pointed out, most including mine have Ash Grey plastic side skirts where the electric seat switch packs are. Those look like the Sandstone ones found on a regular 75 to me, they may be genuine factory issue seats, or re-covered/replaced by a previous owner, if I knew the trim code from the donor car it might shed some light