26x50 rims.
You have 3 options.
I can make some(the price is in the 4 digit area though, since they are VERY labor intensive to make from scratch).
Felt makes 26x50 rims(don't know if they are powdercoated or painted).
3G makes 26x50 rims(again don't know if they come powdered or painted).
If they are powder coated, painted, or anodized, you can strip them and polish them.
Sand them down or use a paint stripper(sanding takes hour and hours to get it to a fine enough grit). Either way will work though. Then buff them out.