No reason to aim for the sun. Just shoot whatever you want to get rid of off the plane of the ecliptic and away from Earth's orbit, and you ain't NEVER gonna see it again. Space is big.

This is why launching spare billionaires into space is such a good idea. A one way trip in the right direction, and it will be billions of years before they bother anyone again, let alone encounter solid matter bigger than a grain of sand.

Sure it's expensive, but it's the only way to be sure.