Would be good if you put your location in your profile. Have you looked into getting your Teins recond? Plenty of Stagea stuff for sale I have even posted shocks from here (Auckland, New Zealand ) to Aus so no need to be at your wits end - stay cool = there is a solution!
Is there a suspension shop within range? They may be able to swap out your shocks retaining the stock springs and tops and using common brands of shocks. Shocks only last about 80,000km or less under rough use so second hand stuff is no good anyway.