I don't have any opinions but I do have some suggestions.
I recommend Tony Shelton Dealing School. I might be a little biased here since this is where I personally received my own dealing certification back in 2018. Management has since changed and many improvements have been made to the school since when I wen't. I paid roughly $900 to get my certificate and dealt the WSOP in 2018,2019, and 2021.
A couple of other one's that exist are:
CEG
https://cegdealers.com
West Coast Dealing
http://www.westcoastdealingschool.com/
PCI
https://www.pcidealerschool.com/
There are a few others that exist as well, however, these are the ones that are the more popular and well-known amongst the dealing community. I believe PCI was actually started by one of my dealing instructors prior students at Tony Shelton's. I could be mistaken though.
Feel free to send me a pm.
Hope this helps.