The Nissan ball bearing units are smaller than most Garrett T03's found in Europe. They also weren't available in EU or USA so chances are you won't see one anyhow.
The Grand National turbos are sort of a T03/T04B hybrid. Being in Europe you probably won't find any of those either.
The Volvos are Saabs are ok but have smallish compressor wheels and often have .48 turbine A/R's; kind of small, really.
I would stay away from big diesel units since the A/R's tend to be extremely large; usually over 1.00. That coupled with the high polar moment of a big turbine makes them a lot less snappy than a pair of T03's.
You should be able to find lots of the Ford 2.3L vehicles' turbos however, as there were so many of them. They have one of the largest T03 compressor wheels out there (~1.8" inlet bore) and a decent turbine wheel by T03 standards. Stick cars usually have .63 turbine A/R, and automatic trans cars have .48 turbine A/R. A bunch of people use these on 302's with a good degree of success.
Whatever you pick, make sure the shaft play isn't excessive (wheels shouldn't touch the housings) and the shaft still spins easily. If you can, pull off the turbine housing and make sure there's no sign of
oil (burnt or otherwise) leakage out of the turbine end. Also, a lot of T03's crack along the parting line in the turbine housing casting; look inside the turbine inlet for cracks radiating from the tongue and running back toward the inlet. They still work ok cracked, but it's preferable to run an uncracked one of course.
Chris
P.S. - stay away from the Chrysler 2.2L turbochargers (did you get those vehicles over there?). They are small compressor (50-trim), .48 turbine A/R, and a unique turbine inlet flange. That flange means that whatever header arrangement you fabricate to bolt to the turbo, will have to be modified back to the normal T03 flange everyone else on the planet uses, when you go to upgrade.