No start 340

Does your balancer have a timing tape? Is the balancer correct? You can Google how to adj your valves in 7 90° turns of the crankshaft. Have you thought of leak down testing ? It will tell you eactly where the air leak is.
You can have an engine builder assemble an engine, or someone build your whole car for you, but unless you can find someone to maintain it for you, you will have to learn at some point to do most of it yourself. Not trying to be a smart ***, I am still learning too, always will be.