I'm having trouble finding a few shrubs, would anyone here know where I could buy these online? I have a good start on a permaculture food forest going, with ~25 fruit trees and 8 berry bushes, with "chicken grasses" ground cover (my Barnevelders and Muscovies free range there), just need to add a shrub layer. USDA Zone 9 or 10, the plants below were recommended from a couple sources.

Caragana arborescens ("Siberian Pea Shrub")
Leucaena leucocephala ("White Leadtree")
Sambucus cerulea var neomexicana ("New Mexico Blue Elderberry")
Rhus trilobata ("Skunkbush Sumac")
Tithonia diversifolia ("Mexican Sunflower")

Anyone know where I should be looking?

Only one on the list I'm familiar with is the sumac, it grows wild around here, known as littleleaf sumac, it grows into a fair sized bush that likes to grow low and dense, the wild ones here are only OK wildlife food but are very good for cover and nesting. Not sure I'd want them in the chicken ranging area, cover means 2 things good for prey to hide in and also good for predator to hide to ambush from.

Lawyer Nursery had the caragana and the skunk bush.

I had thought the Siberian Pea Shrub was suitable for zone 9 but was told differently today. I might try one just to see...

Caragana doesn't do well in my heat.
Leucaena is toxic to poultry (might be able to plant it for rabbits and keep it away from the poultry)

I found a couple each of the other three from a nursery in Texas, waiting to hear shipping costs for 1.5G plants.