You have only removed the Handle assembly [porcelain cross accent and chrome handle base], and the chrome threaded escutcheon sleeve (retaining nut) in your pictures. That threaded sleeve is the only faucet part holding the large chrome cover plate or escutcheon on, except maybe some caulking. Remove the that cover plate and you should find a flange with 4 screws around that threaded plastic piece. Removing these screws will allow you to remove that front plastic part of the housing, a large O-ring, a small O-ring, the plastic stem extension, the balancing spool cartridge, and finally two small oblong O-rings.
That is a pressure ballanced price pfister faucet, It may have built in stops (screw driver slot on each side of the control valve) to turn off the water while you make your repairs. Be sure to turn off the water before removing the four screws.
Good luck finding the repair parts, hope they are more plentiful in your area.