The top finish can be replaced quite easily, BUT you have to be sure initially that this is the problem you are dealing with.
Shininess on an old leather can be caused just by wear and friction and it MAY be that with a good clean and protect (not condition) it will restore it back to its former glory.
It could also have been caused by previous cleaning products that have built up a layer on the surface, this may or may not have damaged the finish.
This is certainly a case where you need to diagnose the cause of the problems before you start to even clean it.
If it is now feeling like a fabric this can also be caused by long term use as it may have stripped the surface causing a 'nubuck' effect on the leather. This is much more complex to resolve.
The suite may also need recolouring before refinishing which would need to be left to a leather technician. You can buy products off the internet for recolouring leather (some professional, some not) but without the correct instructions and knowledge for preparation and application it can go badly wrong and you are left with an expensive problem. Not many professionals will be then willing to come in and correct your mistakes for obvious reasons.
If we can be of help please contact us.
Regards
Judy