I have just been pleasantly surprised.
I have a Swarovski 4-16 x 50 that had a turret cap missing when I bought it second hand. I phoned SWAROVSKI OPTICS UK to see about getting a replacement and was very happy to be told, two, would be sent free of charge in today's post.
Credit where credit is due and hat's off to them.
(I just hope they get the right size out to me as they don't seem to be standard size.)