Anyone with experience in Electron Beam welders

A customer has approached me install an Electron Beam welding machine to run some production parts. It would appear to me that all these machines are custom made.
I was thinking to buy the EB welding head and power supply/controls and build my own machine, does anyone know of where I can buy these items?
Any suugestions on this process or build ideas?
Other than a few hours of net searching and reading I know nothing about the process, any help would be appreciated.

Thanks