Antique 1930s Standard Devoro Toilet Repair Help (pleaseee)

I am visiting my father and he has an “out of order” hand written sign on the bathroom door. That kills me. I’ve had many, many plumbers come by (in the Miami area) and none of them have known what to do with the antique toilet, the house was built in 1936. I think there are a couple things wrong with the tank, and I am happy to replace all of the parts but I don’t even know where to get started. At first, the thing that floats on the top to tell when it’s full was getting stuck. Now the plastic thing that covers the drain at the bottom doesn’t close all the way, so it just keeps running.
a) are there any great antique toilet expert plumbers in Miami who can help with this?
b) anything else you suggest
Thank you so much. It might seem like a small thing but honestly, it would be so helpful.
Thank you, thank you, and have a blessed day.
Replies
If it were me I’d give this place a shot at an answer
https://terrylove.com/forums/index.php?forums/plumbing-forum-professional-diy-advice.6/
Do come back if you get lucky.