Making your own broth (stock) is great as you know exactly what’s going into it! Your best bet for bones is talking to your local butcher and asking for a mix of meaty and jointy bones. Meaty for flavour and jointy for collagen and other connective tissues which break down. All bones are good sources of nutrients. For beef stock, you’ll almost always be able to get oxtail and beef rib bones from your local butcher and those together will be fine. If your ribs come with meat on them by all means cook them up and eat the meat off them first before putting them in the stock. They can even be frozen before you put them in, so you don’t have to have your ribs for breakfast 
The best way to cook beef ribs is low and slow and for Keto, make a dry rub which will add flavour without carbs.
General consensus is to roast any previously uncooked the bones for around an hour before putting them into your stock as that helps to bring out the flavour. Don’t forget to put the juices from the roasting into the stock pot.
This is the recipe I use…
I used to do mine on the hob in a big pot and while that did yield a good amount of lovely gelantenous stock I’ve recently got an Instant Pot pressure cooker and what used to take 6 hours on the hob now takes 2 and I can do it in smaller batches and produce arguably better stock.
It will take a day or so for the stock to fully set into a jelly, after which you can take the fat from the top and use that for cooking veg or other things in.
Your stock will keep in the fridge for a couple of weeks or freeze for up to 3 months. I use old cream containers to make 300ml cup-sized portions for the freezer. Once frozen I then loosen from the pot by running it under the hot tap for a few seconds before popping the contents into a tightly sealed container to take into the office on the days which I fast. You don’t want your thawed stock leaking anywhere unless you want a pack of dogs following you around
Hope that helps 
