The 4 wire keypads come with all new 600,601 panels and will work on the 595 as the later models used the 4 wire. They are readily available to order on the net.
The 2 x WiFi fobs are programmed through the wireless receiver and Prox fobs held in the panel memory.
A simple swap of keypad will have your system up and running again. New 4 wire keypads are blue backlight.