The TS2 is the staple of most bike shop workshops, they’re “good enough”, certainly for everyday servicing and wheelbuilding. You can use them without the adjustable base, I know mechanics who just clamp the bottom of the TS2 in a bench vice, but the base does make it more comfortable – you can angle the stand forwards and backwards.
If it’s the aluminium block to re-centre the stand you’re talking about, you don’t really need that, just any properly dished wheel. However, if you want to accurately check the wheel dishing, you’re best off getting something like one of the Park WAG tools.
Certainly if you’re building at most two wheels a year, I’d suggesting looking for a second-hand TS-2. Or as a cheaper alternative, the Minoura folding stands are pretty good and take up a lot less space when not in use.
Or, if money’s no object… £1700? 😉
http://www.pklie.de/truing_stand.html