Where can I buy a cheap dash board for a dodge ram 1500 ?

Depends on the year. Most all vehicles built from 2000 on have the VIN programmed into them, and are not interchangeable with others, ( no junk yard swaps ) often the dealer is the only way to get them. They are on an exchange basis,( either they need yours as a core, or they will repair yours and send it back ) that means the vehicle will have to be down while it's on order, as the milage is required by law to be accurate within the mechanical limits of the odometer.