In no particular order, Bangkok Bank, Kasikorn and SCB. You can check on their websites for the information pertaining to your circumstances and the advantages for foreigners using these banks as opposed to others. Good luck to you.
Transferring 65k(+) FTT monthly to show 12 deposits for IO Non-O Retirement extension.
I then transfer the deposit to another account keeping a small balance to pay bank, IO extension of stay / re-entry permit fees etc.
This way Immigration cannot see my monthly expenditure; getting about two pages of my bank book, with a very short corroborative bank statement detailing the total deposits and balance come renewal time.
Your guess is as good as anybody's. Without confirmation from the OP it's all hearsay. But what is factual as you state, is the 60 days extension of stay expires on 14 May 2023.