For a June 1964 trip that would have her comming right out of dry dock because she was painted white in April/May of 1964, but it could still be possible.
This web site shows the ship and the history of the ship, although this person asks for no requests for boarding history, they may have it and always worth a request.
Also if he came into the US though customs and immigration they would have a complete history of where he entered, when, and using wht papers.
Orient Line SS Oronsay
This is a fairly old site, but here were some formal passenters in 1964
*prior to April but who knows they may know info on it
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