Looking for Advice - Vintage Tudor 7803 Purchase

[jwiner]

First post here. Thanks in advance for reading.
I am new to the vintage watch world but after lots of research and searching I found a mint condition Tudor oyster shock resisting ref. 7803. Everything checked out and was 100% original so I bought it. When it arrives the crown would not screw down. Wouldn't even start to thread. It would almost catch then pop back out. It also skipped a bit when turning the crown to change the time.
The gentlemen who sold it to me apologized and offered to take it back to the watchmaker who "service" it at no cost. After a few weeks he said they have replaced the crown and tube.

I'm looking for advice, as he told me that the crown replaced is original but does not bare the "Oyster Patent" it had before, instead baring the Rolex coronet.
I know many vintage Tudor's have this coronet, but can anyone let me know if this repair/replacement has decreased the value of the watch significantly as it is not 100% original now?
He mentioned his watchmaker used to work for Rolex and told him that replacing the original oyster patent crown and tube are problematic and in addition to being impossible to find. He stated this is a normal change Rolex would make if the problem arose.
Just want to check with any experts here the validity of this, so I can rest assure I have a nice vintage piece that will retain value.

Thanks,
-Josh-