There isn't any 4-speed transmission that will swap in easily.
The only option I know of would be a 42RLE from a TJ, but the issue with that is that it's computer controlled, so you'd need to swap in basically the entire engine, wiring harness, and transmission from the TJ.
That would be a huge task, and a lot of it wouldn't work (such as the dash harness).
And that of course doesn't even take into account that the 42RLE is a pretty shitty transmission in general (I've owned a number of them).