Well suspension wise just get a Eibach pro kit fitted, would do the same thing..
Wheel wise be a bit more original and go for some 15s or 16s which aren't standard fit. The tyres make the difference (tip: don't go for Goodyear) so don't skimp on cheap tyres.
Seat wise it would be an impressive waste of money - half the fun is the being thrown about in the 1.2.
How about tuning the 1.2 engine? You can get the 1.2 engine to 90bhp for about £700, and with that power due to the engine/car ratio being lighter, it would be just as quick as the 100hp!
Or just get a 100hp..seriously please don't go wasting your money trying to make your 1.2 what it isn't, a 100hp - build on what it is and the advantages it has (less weight, better gearing) or even better get a multijet!!.