Power window motors in the Fiero are the same from like years of Firebirds and Camaros and many GM cars of the late '80s and early '90s. Finding good motors in salvage yard should be easy. Motors are still available from GM but are pricey. Salvaged motors from the rear doors in 4-door GM cars are generally in excellent condition.
Power window and power mirror switches are exactly the same in some years of Firebirds and Camaros. Since all these electrical items are the same, so are the connectors.
Manually powered window cranks, called "regulators", can be purchased new from auto parts stores carrying the Help! brand of small parts and accessories. The regulator for all Fieros is Help! 76903.