First of all, the top of line JIC coilover for JZA80 Supra, FLT-A2, does not cost $3000. It retails for 195,000 Yen, which is about $1700 using 115:1 FX rate. You can buy them new for ~130,000 Yen ($1200) or less in Japan.
All JIC coilovers are height adjustable. Only FLT-A2 can adjust damping levels (15 levels). JIC coilovers are very popular among drifters in Japan, the circuit racers prefer other brands. Having said that, FLT-A2 for JZA80 comes standard with 20 kg/mm front springs and 12 kg/mm rear springs. That's ~1100 lb/inch front and ~680 lb/inch rear. You'll get a pretty rough ride on the street.
JIC also make a rear toe adjustment link for the 80 Supra.
--Joey