rug size depends on the room and how much coverage you want. 12x13 room means a 8x10 rug is going to cover most of the floor. to get an idea, measure out the rug size w/painters tape. this will give you a visual. post a picture of the room and the sofa, and any other furniture in there. as for the rug, you can check here on Houzz. narrow it down by Abstract, and then the colors

Hi guys! So we just moved into apartment and it is all wood floors, for the bedroom I want to put down a rug for whole room/basically cover the floors to make it look carpeted. Obviously it won’t look the same as if it were because it may not reach whole perimeter of the room, I’m fine fine with some wood showing on edges. But would look like it to all be covered w something similar to a carpet (without installing permanent carpet ) if that makes sense. I was just browsing online to see what kind of rug material / style I like , and I gravitate towards neutral. I would like something like this in regards to material/color. Never bought a rug before so no idea lol.

Do you want those exact rugs or do you want something similar?

There are literally hundreds of rugs like this…on the internet at very good prices…try looking at Wayfair and Rugs USA …to reassure yourself ..most patterns are still being made today…so yours being old ….doesn’t make it impossible to replace…if it comes to that…hate to say this but i would avoid Ballard as they will sell you the same rugs with less choices and at a much higher mark up..