Product review (4 stars): Worth a shot and it paid off
1) The suggested models are useless, as they are washers and air conditioners and stuff. My unit is a side-by-side fridge/freezer model number FRS3R3JW0. That probably doesn't help anyone else, but I CAN confirm the dimensions listed. The width of my butter shelf sides was about 12" and the height seemed to match up as well.

The longer left edge in the photo provided is actually the front. The notches in the corners sit on the butter shelf, and the door edge actually falls in front of the shelf front edge. The rounded corner on the right side is the part that rolls back behind the shelf when you open the door. If your dimensions seem right, order it and give it a shot - you can always return it.

2) I bought it "used" which ended up fine (and a lot cheaper). It was clean and unscratched and it was just fine.