The earliest Panteras came with Ariston shocks, and then later with Telecar. In both cases the fronts were painted black and rears are blue. All four springs were painted black in both cases. They all had rubber bushings with a steel sleeve inside a housing that was part of the shock. Neither the Ariston or Telecar can be rebuilt. And neither were ride height adjustable. Yours have a hiem joint setup for bushings, they are ride height adjustable, and are painted yellow. They might be Koni and if so can probably be rebuilt if desired. In any case they are likely aftermarket and it might be better to simply to replace them with a modern shock like the QA1 from one our vendors that are already setup for Pantera with correct heim joint bushings and appropriate spring rates.
If they have not leaked out then you might be able to clean them up and use them as is. The leak out would be evident by dirty oil accumulated around the top of the shock.