Hi Sam, welcome to OL!
There are three basic things to try for a better ride over the rough stuff:
1. Drive Slower
2. Reduce your tyre pressures (where practical.)
3. Improve your suspension.
New shocks may be enough to provide a better ride, but they won't help much if your springs are too stiff.
I wouldn't bother with new torsion bars, unless you already have aftermarket units; these are likely to be too stiff, and a set of "worn" originals will probably be softer and more supple off-road.
Replacement leaf springs can get expensive in a hurry - hopefully somebody can give you some better tips than I can!
Cheers,
Scott