Most ALL the stock parts are redily available from your local auto part stores (Pep Boys, Kragan, O'Reily, etc). Before you get all distressed about finding parts, why don't you just go into the auto part store FIRST, and if they cant help you then consult the forum.
As far as your rear suspension goes, its all available at the auto part store. Bearings, hubs, brakes, axels, half shafts, sensors, shocks, struts, steering arms (the list goes on forever), are ALL available from the auto part stores. All you need to tell them is the year, make and model of the car, engine size and transmission/gearbox type and they can look up EVERYTHING on the car.
Posting pictures of the exterior of the car does absolutely nothing to help identify the suspension type. I will bet if its a "bump stop" rear suspension then its all stock Fiero. Nobody to my knowledge would recreate an aftermarket bump stop suspension for these cars since everybody was trying to get rid of it in the first place, being such a bad design and the inherent problems associated with it.
Also, go buy yourself one of these books.