Anodizing aluminum is a bit more intensive then titanium, and not many in the knife world do it (especially in a home shop, involves acids). But there are some options out there if you really look.
As an alternative, in the gun sector there is a chemical by Birchwood Casey called aluminum black. You could clean the scratched up areas well and apply the chemical per the instructions. It will turn them black. It will not be the same matte ano finish, but would hide the scratches well, and doesn't require stripping and re-finishing the entire handle.
I have some, and have done it quite a few times. If you dont want to DIY, hit me up.