hi djb, thanks for asking. Yes, I found two of the last 22T rings on ebay.
I got back from Greece a few days ago and bike is still in its box.
Good, may the switch be straightforward.
Make sure the FD inner limit screw is set so it's just, just past rubbing the chain on the biggest cog and then see how quick downshifts go (in case you need to get a chain catcher gizmo)