Best of luck finding a source of dun/khaki for your project! I know it's a kind of rare gene, part of the reason I'm trying to keep it going in my little flock. I'm not sure how many other Aloha breeders have dun in their gene pools, there's not a lot of people breeding Alohas to begin with. I'm not even sure if the person whose flock genetics I hatched my hens from still has any dun birds in their breeding group. I'm lucky to have hatched my hens, I think it would be really cool to create a line of khaki Alohas who lay blue/green eggs.
