I use short ribs. The grocery stores around here will cut the short ribs up to small little bones so they can get more money for the cryovac. I ask the meat department if they have any of the beef short ribs that aren't cut up. They will bring the cryovac out that has 2 racks in it (4 bones each) and ask if that is what I'm looking for. I look at the marbling and say yep if i'm happy with it. They weigh it and slap the price tag on it.
Here are the last 2 batches of short ribs I have gotten.