When reports emerged earlier this week suggesting that one of the finest goalscorers in the Premier League could be available for as little of £30 million this summer, the ears of Manchester United supporters pricked up like those of a hungry dog hearing the rustle of a crisp bag. A striker who hit the target 20 times in England’s top flight last term – and 117 times across the previous five seasons combined – was reportedly up for sale for around a third of the price the Red Devils had been quoted in January. But if that felt too good to be true, then that’s probably because it was, Mancheste…