Come on man. Rims are always painted like that. You don't need expensive paint jobs for that. You should use good quality spray paint at 2-3 coats, giving a break of 30-60 minutes each. Rims are not the things which are not touched very often, so don't worry about that. If happens, just spray that spot again, easy peasy.
If you want to invest more, then you have to coarse sand it and then apply primer, after that fine sanding, and then spraying with machine.
IMO all that is not necessary for rims.