Chrome ring model

Hi all
A mate of mine is buying a series 3 and it is a chrome ring model but the outside of the ring has been removed to fit a non-chrome ring headset, I.e. you can’t see the ring now.
What bits would he need to put a new ring on as the headsets are different (lock positions). Would it be just the lower head set or does it go onto the upper part - maybe even horn-cover?
Anyone help?
Spl
A mate of mine is buying a series 3 and it is a chrome ring model but the outside of the ring has been removed to fit a non-chrome ring headset, I.e. you can’t see the ring now.
What bits would he need to put a new ring on as the headsets are different (lock positions). Would it be just the lower head set or does it go onto the upper part - maybe even horn-cover?
Anyone help?
Spl