there was a thread more recently that had a new torque arm style setup. Can't remember what mfgr though. Other than that, many shops are making them for falcons and mustangs but they need to be mod'd to fit these cars narrower frame rails. GrabberGT and a few others around here have mod'd kits you could look at.
Grabber gt and I have the tci 3 link kit cut down. Better off finding a race shop to make something from scratch it will be cheaper and most likely lighter.