Try ebay.

I would go with terrazzo since going with wood would be a poor design choice. I am not a fan of wall to wall carpet for a variety of reasons so that wouldn't be an option for me. Terrazzo is both true to the period and would look great with that style of the home. It is also more of an investment to future buyers as anyone who is looking for a classic MCM home is going to be thrilled to find terrazzo. However, wall to wall would no doubt be cozier but would need replacing fairly frequently

I see this languishing way down on the Design Dilemma queue. That's not good. There is something so wonderful about the light spaciousness of that room that I'd suggest you go for a very light grey -- I think cool will work better with the blue-green range of colours you are thinking of. White trim. I was thinking it might be best to decide on the fireplace when your furniture is in and the walls are painted, but I suspect carrying the wall cover over it will work best, because it really is a rather imposing chunk, isn't it? Not sure about the aqua ceiling .... I'd like to hear others' opinions about that.

@Patricia, here are some realtor photos from the rest of the house (previous owner's furniture, not mine) In this one, you can also see the stairway paint color (could I simply extend that one into the living room?)