I feel like Bournemouth would be a good fit for him, would suit their style of play IMO and they need an upgrade at RW. Plus they're good at developing young players (and have an excellent manager currently) and it's right next door to Southampton if being away from home is still an issue for him.
Obviously it goes without saying, they aren't going to be able to afford to stump up anywhere near £100m but nobody in their right mind would.
I'm not sure I see him going much higher than that immediately. Villa could be another option as they are lacking quality others in that position as well, but I don't think he'll provide the likes of Chelsea, Liverpool, Newcastle what they need exactly as they'll probably be looking for more proven goals and end product in that position.