Hi,
New and used motors, controllers, cords can be gotten fairly inexpensively on ebay or the internet sewing supplies like sew-classic. The expensive part will enter in if you have to take the machine in to be serviced. Many enthusiasts have tons of good controllers and motors from hand crank conversions. Good chance the motor is fine, like the machines they were built to last though check the little bit of wiring carefully. Never hurts to negotiate and hem and haw about all the money it will cost to fix up
Jon