Stripping the anodizing is the worst choice. Check into the cost and lead time before you make an expensive decision.
If you paint or coat it, anodizing is the industry standard primer, even on light commercial fabrication work. Don't remove anodizing, as now the surface would need recoating with a primer that has to stick to a bare metal surface that is reactive to oxygen. No coating is 100% guaranteed non-porous, but milspec anodizing is amazingly tough and has to be literally ground off.
The better choice is paint or coating. At the lower end of cost, an auto paint shop can color match and mix a 1/2 pint of paint you can apply at home. With a coat or two of clear over it, it will be significantly more durable than most shooters know or have experienced. Plus, the anodizing remains to prevent further corrosion. Any of the marketed expensive paints and coatings for guns would work, and come in specific colors. Some are even baked on at low temps to improve scuff resistance.
Buy the stock furniture first, as then you could match or contrast the colors of the metal parts as you wish. Or, have them painted to match the intended choice, although paints for plastic are more difficult to source. Using an adhesion promoter like Bulldog, and getting paint used on polymer car parts would help.
Anodizing, not so much, you will be restricted to the specific color that shop can provide, and the lead time could be extensive waiting for enough other customers who want that same shade on their custom parts to meet the minimum needed for that batch of treatment - ie chemicals. It's not a small batch process someone can knock out in a weeks time, it's mass production scheduling for hundreds, if not thousands of parts.
The most experienced nitride appliers for color supply the custom knife business. It would take some research to find those willing to process a small batch of gun parts that would likely need to have the existing parkerizing first removed to apply the color. That's a lot of tedious hand labor, buffing, etc.
