Customer name changed to Proper case with exception

Hi,

I have a column with supplier Names. I need to make sure that all names are in Proper case. I can run Proper formula but it will change everything. I have exception name like ABC Castings Pty Ltd which need to stay as it is and do not want to turn in Abc Castings Pty Ltd.

Does anyone know what will be work around and how it can be durable?

I have attached one part of the spreadsheet.

Please note I have 30,000 lines to change.

Thanks in advance,
-Krs