Hello, I would like to thank you all for the many responses and the warm welcome to the forums.
The end of the Mark V story is that sadly the seller did not respond to my email about taking it out of the stock to check for "salt wood".
Now I don't want to assume ill intent on his part - on some rifles I don't like taking them out of the stock myself - but the risk wasn't worth getting in a fight with another bidder over.
For now I'm going to postpone the .300 Weatherby to a point in time when I'll be able to feed it better. Might also look for one with nice wood on it then.
But by then I'll know what to look for. And I now know what a Canjar trigger is.
I was born in Wurzburg in 1963, so welcome!
What a coincedence! Würzburg is only about 50 miles from where I live.