41te problems '04 Caravan 2.4l

I’ve got a 41te here. It’s from my 2.4l '04 Dodge Caravan. You can see the corrosion on the casing. It came off in chunks. I wanted to rebuild my transmission but once I saw what was causing the damage I assumed the corrosion would just continue and that this case was done for.
Now, used transmissions… I can purchase one for $125 at the junk yard. I was thinking of maybe just rebuilding that one or maybe even just ordering a brand new case for even less money and just swapping the parts that are still good and purchasing the ones I was going to replace anyways… We have $1000… We can’t buy a new car. We can’t pay anybody for help, although I usually do all my own work anyways. I can’t seem to find any rebuilts at our price range. I also need some information regarding this “quick learn”… is it absolutely necessary? If anybody has any information about any of this, it’s my first attempt at a rebuild, I decided to give this a shot, any help at all would be greatly appreciated… Thanks…

I don’t know enough to advise you on the repairs, but I have found the minivan forum at allpar.com very helpful when I’ve had questions about my 2007 or former 1999 Chrysler Corp. minivans. Good luck with your project.

Thank you I am going to take a look