Sears/Craftsman never made their own pumps as far as I am aware. In all likelihood, one of the major manufacturers made it and brand labelled it for Craftsman. With some internet sleuthing you ought to be able to find the OEM's (not Craftsman) equivalent, or present day equivalent. Then, do a deeper dive into the specs. This is all in advance of you pulling the existing one.
Once you've got a good replacement candidate identified, buy it and start preparing for the changeout. In generally similar cases like this, I've bought off of Amazon due to their liberal return policy, in case I did end up buying the wrong thing.
I just went through this with a 36" tall freestanding sump pump. Granted, my situation was a lot easier than a downhole pump. I did a bunch of upfront homework and with a little luck, ended up getting a brand new pump that was the spitting image of the old one. Also, once replaced, don't toss the old pump for a while. Get the new one installed and run it for a month or so. Once you are satisfied there are no issues, off to the dump the old one goes. Save all documentation and take pictures of both the old and the new pump to refer back to in the future, if needed. I've done that and it makes it Sooooo much easier if any issues come up.