It depends on if you have the 4 speed auto or CVT as these likely have different half shaft lengths, and there are different sizes of CV & outer hub. Depending on which box you choose, you will need to replace some or all of these.
There are 3 possible gearbox sizes and a viscous LSD option that could be bolted in to the 1L motor.
RS5F41A Used in K10 and on 1992-~1999 K11 with 1L. No oil fill plug in front.
RS5F30A Used on E & GA motors in Pulsar/Sunny etc, & standard box for 1.3L & post 1999 K11
RS5F31A Used on E15ET & GA16 motors
RS5F31V Used on some CA16DE, CA18DE, Holden 1.8L N13, & rare option for K11. LHS inner CV has longer stub shaft. Apparently interchangeable with CVT half shafts, ref EVLGTI K11.
CG & GA bell housing bolt pattern is the same (E & CA not).
30 & 31 boxes can both use the 30 mount.
For the 1L motor, unless one of the other boxes was easier to find/cheaper for some reason, I'd stick with the RS5F41A. Smaller, lighter, ratios it comes with will suit 1L motor.
As for prices, I know nothing about Greece. In NZ the parts would cost NZ$150 upwards from a pull it out yourself wrecker, depending on which box is chosen, clutch & flywheel, clutch pedal & how many mounts, shafts, CV's, gear selector is needed. Buying a whole wreck can be a good way of getting cheap parts & on selling it once you've sold/taken all bits you want. It is fairly easy work to change & could be done in a day, paying a garage to change it would probably be NZ$500-$1000. It may be cheaper & easier to sell your auto & buy a 5spd?
Maybe somebody should put this information in the articles section, it gets asked regularly. In previous posts there have been some good comparison pictures of shafts & boxes.
