If we have to sell him, and I'm dead set against it, 50 million + Dzeko. Then use the 50 million to buy two world class midfielders + the best up and coming 18-20 year old keeper in Europe. Again though, we really really shouldn't.
50m would give you Dries Mertens, Theo Walcott and still have change left over to by some up and coming shit hot talent. I also think Dzeko is quite underrated since his move to England. 50m plus Dezko wouldn't be the end of the world.