They say several hundred years since a whale like this has been seen near Israel ? does that mean that they had records of whales being in that area 700-800 years ago ?
No, I'm pretty sure it just means that there are records - ship's whaling logs, probably - going back to the late 17th century that noted gray whale sightings/killings in the Atlantic.
This isn't the first sighting off Israel in 300ish years, it's the first sighting anywhere in the Atlantic, to include the Mediterranean which of course is only accessible to whales from the Atlantic.