It seems as though the film makers of Kill a Dragon couldn't be bothered with organising their own boat tour and instead decided to hijack an existing one. I guess it is fair enough though because the character played by Aldo Ray in the film is actually a tour guide for the hotel.
Yes, the Wan Fu was a real boat and it was operated by the HongKong Hilton - no need to create fake boat names and signposts for these shots.
A few familiar shots of Aberdeen Harbour above (that's Also Ray with the red blazer). In the following shots we catch a small glimpse of both the Sea Palace and Tai Pak floating restaurants.
Here are a couple of further pictures that show the Wan Fu circa 1990 - just a few years before the Hilton was demolished.
I have no idea what happened to it afterwards, perhaps it stayed on with a private owner or was sold overseas. If anyone can fill us in on what happened to it then please feel free to leave a comment below. I hope it didn't go the same way as the Osprey :-(