It'd be another poor decision by Levy if he insists on not selling to PL 'rivals', this is followed by many others that he could have got rid for decent sums with the likes of Rose, Dier, Alderweireld, Modric, etc.
Spurs won't win any trophies or get top 4 with or without Kane, they should take what they can from his sale and re-invest into the squad.
It'd be a wise move for Spurs to follow Leicester's / Dortmund's transfer strategies by bringing in up and coming young talents when top clubs can't afford to give these kids time to develop on the pitch.