The only bolt-in would be a T18 or T18a from a pre-1980 CJ
If you are willing to swap Tcases too, the T-176 4 speed and D300 from a 1980+ CJ would be nice. The gearing in the T-176 works great with a 258, and the lower first gear combined with the D300s better low-range would improve your crawl ratio by alot. An SR4, T4, or T5 from a 1980+ CJ could be swapped in too using the D300 that came behind them. Those three are kind of on the weak side though. With that setup you could use factory driveshafts from a 80+ CJ5 that came with whatever transmission you choose.
Those are the factory options.....with adapters, you can put anything you want in there.