Shaw cost near as much, while Everton refused 26m for Stones. Kane is a striker, they cost far more.His value would probably drop to around £65m if he got 10 goals the whole season.
But seriously I'd put his real value currently at maximum £30m including English tax and to be fair I think he is currently £15m - £20m player.
I think that he is probably a 40-50m player. Sterling cost 49m and is a better player, but on the other side Kane seems a top professional, not a cnut like Sterling.