I've got a workaround for this!
My solution was to wrap VST plug-in's under Snow Leopard. The VST - AU Wrapper might work under Lion and Mountain Lion, but I know for a fact that it functions fine on Snow Leopard. Apparently, you can wrap VST's under Snow Leopard, and just migrate the wrapped plugs over to your Mavericks OS and they work fine; in Logic Pro at least! It might be useful to know that I then used 32 Lives to wrap these AU-wrapped, 32-bit VST's in Logic.
I initially attempted to just use my existing, wrapped plugs after migrating to Mavericks, but I made an apparently crucial mistake: I placed my wrapped plug-ins in the User/Library/Audio/Plug-in folder. Apparently, these plug-ins MUST be placed in the System/Library/Audio/Plug-in folder! I never realized it before, but apparently, some Audio Units will only work in one location vs. another. Remember this, and hopefully this workaround works for you too!
Also, I heard that the program BatCHMod might work to undo the Components folder permissions set up under Mavericks. I don't need to try this now, but if someone else does, and it works, share your results! It's a free download.