Hi mate - that thread should answer your queries but the UK TT was available as a single model only and had no designation other than being a UK TT. The SZ, SZ-R, RZ, RZ-S, GZ, VVTI and Aerotop (SZ and GZ) are all JDM (Japanese Domestic Market) cars (ie. imports if here in the UK). Insurance is usually the only practical reason to choose a UK TT over a J-Spec TT as both offer unrivalled power and driving fun.
UK cars are available under 10K - they take some finding as only 600 or so were sold and were only available from 1993 to 1996.
Happy hunting and be patient if you want a good car - its better financial sense in the long run!