The calipers are Girling, the wire is a simple wear indicator, virtually no one bothers with that in replacement pads.
There's a lot of historical information on this site and the search function is pretty good. There's also a sticky on brakes that is worth reading.
Also lots of other good resources online Mike Daley's site is just one example;
http://www.panteraplace.com/Page9.htm
If you area POCA member you get access to all the technical bulletins and information, plus newsletters with tech articles etc. A lot for $75 annually www.poca.com
Most folks are using the Porterfield pads in a RS4 compound I think. If ordering you need to tell them it is for a Pantera and they will weld the locating nub on the rear pad. Caliper rebuild kits are readily available from the Pantera vendors and I saw discussion someone was selling replacement pistons as well now.
Julian
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