I'm not able to use the link. I did make a Bosom Buddy (free pattern from By Annie). Not due to surgery, but due to the size/location of the girls. Seatbelts always slid up and were nearly across my neck. This keeps it at the level/angle that it should be so is much more comfortable.
It doesn't have a lot of padding, but I'm sure you could add another couple of layers of the foam. Here is the link. You do have to sign up for an account (give your email) to get the link to the tutorial video & pattern. When I made it, I used only the pattern, but video might be nice to follow along.
https://www.byannie.com/slides/free-...erns-videos-98