
Okay, admittedly this item is less a genuine retro item and more a denizen of the land of tacky neo-retro kitsch populated by ceramic Betty Boops and plastic Elvis clocks, but I still thought it was kind of neato.
I actually looked up this item because of "Seinfeld." While watching the episode where Kramer reverses his peephole, I was impressed by Kramer's sofa, which is much like the one above. A quick internet search for "car sofa" turned up all colors shapes and sizes.
There are lots of them on ebay for the somewhat steep price of $1500-2500. On the site EarlStation.com they have a broader array of retro car-inspired furnishings, including bars, clocks and chairs.