They are plenty of varieties that do pretty well here in L.A. Bonsai nurseries have them all over the place. Young trees are cheap.
But the trunks that you are showing in those pictures get quite expensive very fast. They can cost a small fortune. Crab apple is not like trident maple. It takes a long time to get a big trunk. Some grafted varieties grow faster. The key with those grafted ones, is to have a perfect and very low graft. But if well done, they look great, and you don't have to wait 20 years to grow a decent trunk.
Regarding the price, a tree that looks like those in your pictures, and of similar size, would fetch at least $1000, and possibly two of three times more, depending of the quality and detailed features. A raw trunk, that has no branches, would cost you a few hundred dollars. But then you need to spend at least 5 years, developing the branches, if you know how to do it.