How much would the items and servicing in putting a rock tumbler and an ignition cost?

For a 1999 Chevy Malibu- approx how much would the two parts be and would they be easy to just have a someone do it out of a shop or do these require special tools in a shop and how long can you say they would take to repair? For buying the car for $300 is it worth it? Please someone that may know or has an idea- could i have your input?? Thank you in advance.