Is it permissible to sell a mummified Pharaonic corpse as an artifact, and to sell the items found with it, such as coins and vessels, and so on?

There is no harm in selling the aforementioned equipment to whoever officially owns it, as long as it is not inherently unlawful. As for selling a corpse, it is impermissible because we are commanded to bury corpses, whether they belong to Muslims or disbelievers. Furthermore, selling the likeness of such individuals and their relics contains an element of glorification towards them.