Hi Marcus,
Replacing the vinyl cover is quite straight forward and I am sure the retaining strip should be OK to use again. The weather strips are often damaged by the soft top being raising and lowering into the stowage area a few thousand times over the last 50 years. I would also replace it.
Replacement of the soft top naturally gets more attention than the cover, most probably because it is a little more complicated as well as much more expensive, if you screw up.
Replacing the soft top is not a big deal, ONCE YOU HAVE DONE A FEW. If you have done a MGA or two, you should be OK.
My first one was a 220SE Cabrio. I did not have the courage to rip off the rotten fabric.
Instead, I dissected, examined and studied every little piece. I have done a few since (15 or so, mostly 190SL’s, Pagodas and Cabrios) and just love the challenge. Yes, it still is a bit of a challenge, but what a thrill to step back and look at a well fitted top.
Regards
Chris