I had a local upholsterer/car trimmer repair the seat bolster on mine. He removed the seat, stripped it down, turned it inside out and machine stitched it back together before re-assembling and replacing. Cost £50 and took half a day. Leather nor recoloured but stitching good as new and ready for the next 100,000 miles.
Recolouring the leather can be done as a separate exercise but, to my mind, it is the patina of wear and so long as the seat is structurally sound, which it now is, I'm not bothered.