I need help to identify this handleset. Please do not suggest replacement because the homeowner's association will not allow that. I need to replace the thumb piece but cannot order it without knowing the brand. I found one paper sticker for production date of Nov 1984. It is polished brass handleset with single cylinder lock. The latch plate says Kwikset, but believe prior owner replaced it and Kwikset does not recognize. It needs cleaning which will be tackled when replacing the thumb piece. Problem with it is that the door locks (thumb piece not operable) when slammed but can still be opened with the key at this point. Need to fix ASAP.