If it's only small areas, you can potentially get them repaired, and not the whole wheel.
Places like Wicked Wheels will come out and go it for you on a mobile basis & there are loads of other companies out there.
If you want the entire wheel doing, there are places like The Wheel Specialist but they are quite expensive.
Or you will probably find somewhere local to you that does it for about £40/wheel. You just need to put in some decent Google searches. I searched for ages and couldn't find anywhere near me. Then I changed my search & all of a sudden found Peterborough Trim Repairs who start at £40/wheel.
Best to get it done sooner, rather than later. My wheels have some corrosion on. I kept meaning to get it sorted, and now I think I will have to have all 4 wheels totally re-furbed.