There are heaps of engine swaps....
1.3 sierra
1.6 vitara, 8 valve, 16 valve
1.3 GTi twin cam
4K corolla - Nam got a price for it and gearbox $500?
4AGZE? etc etc etc...
depends how much money u wanna send i spose. I dont think it would be worth spending money getting a 5 spd box mated to a 1L motor because you will hardly ever use 5th gear unless u r going down a hill..
If the 1 litre donk is tuned properly it should hoot along fairly well. Just try a simple tune up
-New plugs
-Points (0.3-0.4mm gap)
-Condensor
-Timing (11 deg BTDC) or u can advance it a little bit..i do
-Adjust the idle if its out (about 850-900 rpm)
-Give it a spray of Nulon carby cleaner....that usually gets mine running nicely
-If its running crap coz of the carby pick up a kit from an auto shop for about $50 -60 and run that through it.....im pretty sure murray could cope doing that
Try that first and see if it helps.....i find with mine if the timing is out, points are closed or carby is clogged it is usually why it runs like a bag of poop.