I bet the cost is high, but you got older trees. Have you looked at the box stores (HD L)? several people find larger cheap one that need a little work. There are several members here that sell some of there young plants and seeds.
We have places we buy around the world and are reliable. KO seeds, Dino adeniums, Riona, Anucha They are on Facebook, They have various sizes you can ask for but shipping can be costly.
Mine are not as big and nice as yours so I will have to wait till they age. I just got seeds from someone, I didn't water the last batch enough, just like when they bloom they need more water.
If you are in South Florida there are several growers (rose) who does the farmers markets. There are several members who grow there too.
My young trees will be shaped and grafted at a later date. I have only been growing them since Feb.
