I got my '89 GTST with Tein HA suspension, 3" exhaust, chipped, HICAS lock and stereo, for around 12K on road (10.5K car, 800 new engine, 300 stamp duty, 600 insure).
Paint's a bit rough, but there's no "damage", so surely a GTS is easy sub-10K else sounds a bit steep to me, but if people are paying it...
Edit: That wasn't imported, bought locally here in Melb, so with RWC it's stacks less hassle than importing. And you actually get to test-drive it yourself.