Vintage patchwork pattern West Bend Thermo-Serv plastic casserole dish

Vintage West Bend Thermo-Serv insulated serving dish with patchwork print lid, 70s or early 80s, never used at all.

It's about 8 1/2" square, nice and clean inside and out. There's two very faintly discolored marks at the sides where the cover was taped to the dish for the last 30 years!