"As my Dad has been saying, he just wishes someone would tell him where he is supposed to go to church."
He should go to the nearest Catholic parish.
If cannot stomach that thought, then he should go to the nearest Eastern Orthodox church.
Because the religion he grew up in does not exist anymore in this country. It's faithful remain, but the church itself in America has moved on to "more important" things, which does not include those beliefs and things that it used to have and do when he was growing up, and that they still have and do at the Latin and Eastern versions of the Holy Catholic and Apostolic Church.
Compromise with Rome or Constantinople or Moscow before you compromise with the Devil.
There is his answer.
Painful as it is.
Are you discounting the Network and Continuing churches that are working to become the third province?
Only if he is high church. Otherwise, a reformed body might be a better fit.