Thanks Mark. I'll run out Monday (plumbing store is closed this weekend) and see if I can find a repair ring like that. If not, I did find it
online.
Any tips on removing the old screws? The heads are badly corroded. Is it best to snip the ring off around them as best as possible and then try to extract them? Once I get the replacement ring, I can see if hacking the old screws off at the sub-floor level is an option such that I can align the new ring so the new screws do not sit over the old. With luck, that will be an option.
As for the grab bars, I have thought about doing that. Thanks for the suggestion.
Thanks again for taking the time to assist me with your advice!